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[Articles Home]  [Add Article]  

High-End HF Transceiver Bargains

James Benedict (N8FVJ) on August 20, 2001
View comments about this article!

Every Ham radio operator wants a high performance HF transceiver. New manufactured products are available, of course, at a price. I noticed the technology has not changed much over the last 10-12 years. The only 'big event' was the addition of DSP (Digital Signal Processing). Audio based DSP is available as an add on option. Four outstanding older transceivers which I consider bargains are available for $800-1200. Keep in mind, I am not setting prices, condition and options set the price. The bargains are the Yaesu FT-990, ICOM IC-765, Ten-Tec Omni V and Kenwood TS-850SAT. The radios were available around the late 80s thru the early 90s. Comparing test results to the new high-end radios, the above radios perform as well, sometimes better. The above radios have a high rating in the eHam Product Review section. I have performed some 'A' to 'B' testing to mid priced receivers and the above are far superior. The best bargains are the radios with a lot of filter options. Often for $150-200 difference some of the radios may have four optional filters. A bargain well worth the extra money. An array of crystal filters adds greatly to the performance.

The OMNI V has an audio based filter that 'completes' this radio. I can reduce the band noise to the point of pulling a signal to 100% copy. Tweaking the passband tuning and tone control custom tunes SSB audio to my ears. I prefer this set up to DSP on SSB signals. For CW work, this radio is known to be outstanding with a pair of 250hz filters. The radio does not have general receive or an auto antenna tuner. The transmitter will not reduce power like others at a 2 to 1 SWR. Removing general receive capacity reduced the phase noise to an ultra low level!

The IC-765 is a hot performer. Not only is the SSB receive great, CW is about as good as it gets. Modify the I.F. shift to the IC-761 passband tuning. Try to find the radio with all the optional crystal filters. Per QST Product Reviews, one of the best five receivers ever measured.

The FT-990 is a good performer. The audio filter is also a plus like the Omni V. The radio is well built, control layout about perfect and less than half the cost of a FT-1000 series of radios. The circuit design is simular to a FT-1000. This radio rates a perfect '5' in the eham reviews for good reason.

The TS-850 surprised the QST Product Review staff when compared to the ultra high performing TS-950 series. Again, try to find this radio with all filter options. Lately, the prices on this radio have been a bargain.

The radios listed do not have a second bulit-in receiver. This is not a big deal for me, although some DXers must have two receivers in one box. If you are upgrading from a low cost transceiver, you will be spoiled forever. One of the best performances of the above receivers is the clean, natural sounding received audio. Good luck.

Member Comments:
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High-End HF Transceiver Bargains  
by W4JPL on August 20, 2001 Mail this to a friend!
In regards to the above mentioned radios, I can attest that the Kenwood TS-850SAT is one of the best radios that Kenwood ever made. I have had (and still have) other radios to compare it to, including the Icom IC756, Yaesu FT-920, Yaesu FT767, and have operated quite a few other radios, and none can touch the trusty old 850 for performance and reliability. No DSP? Pick up one of those cheepo Radio Shack DSP units, and you'll be surprised how well one of those things work as compared to the rigs with the built in DSP like the 756. I also have a Timewave unit, but prefer the Ratshack DSP units. If you can find an 850 in good shape, it's a keeper! 73, John W4JPL
 
High-End HF Transceiver Bargains  
by KK5IB on August 20, 2001 Mail this to a friend!
Not knowing much about HF radio value, I bought as my first radio a Yaesu FT-840. Of course I needed a power supply, keyer for CW, CW filter, FM unit, antenna tuner, SWR meter and DSP filter, some new, some used.
Sold almost all of it and bought a used FT-990. I now have QSK and VOX, not available in 840. Also I have a builtin power supply, keyer, SWR meter, 5 filters instead of 2, two key inputs, RF gain, builtin FM all for about the same price as original 840 equipment and in one box. Added Timewave DSP-59Y in SP-6 Speaker, and for a couple hundred dollars more went from bottom the line to near top of the line. Also have TX Clarifier, didn't know what it was for at first, but for a DX station using split and listening up simply hit TX Clar and tune Clar knob up to DX listening frequency. Noise blanker is superb, only thing I miss about the 840 is that is had true dual bandstacking registers in the VFOs. Recently completed QRP WAS and DXCC with simple wire antennas. My 990 is a keeper.
73,
Darryl, KK5IB
 
High-End HF Transceiver Bargains  
by KG6AMW on August 21, 2001 Mail this to a friend!
This whole thing is confusing to me. When you look at sensitivity and selectivity numbers for all the rigs, they all are close in performance. Same for IF rejection etc. This ranges from FT 840 to FT 1000. So, other than some external bells and whistles the cost of higher models doesn't seem justified. So you add DSP externally, (timewave, MFJ) or look at the new TEN TEC Jupiter. They all use Analogue Devices 2100 series chip and performance increases, a little bit. Some how, I think the king doesn't have clothes. The prices for higher performance rigs don't seem justified.
 
RE: High-End HF Transceiver Bargains  
by VE6XX on August 21, 2001 Mail this to a friend!
Greetings All: Interesting comments by all who saw fit to respond. In response to KG6AMW's reply, I am moved to attempt to explain the signifigance of "high end" receivers.
First of all, permit me to stipulate that the term "high end" generally equates with price, but price alone certainly does not determine whether or not a receiver is state of the art.
Let me make the disclaimer that I do not enjoy "expert" status in the matter of HF radio receiver performance/design/implementation, etc..
I do, however, have some experience, both military & commercial, with very high capability receivers.
The mfrs spec sheets for amateur grade receivers, stating receiver sensitivity, selectivity, dynamic range, etc., quite often are presented in such a manner as to present their product in the most favorable manner. No surprises here. There are an established set of measurement criteria to which commercial & military & scientific receiver mfrs adhere when designing their products. This allows an apples to apples comparison amongst the suite of offerings in the receiver field.Virtually all modern HF receiver designs, whether amateur, commercial or military, enjoy sensitivities that realise reception to the noise floor.
Once an HF receiver has a sensitivity that allows it to receive desired signals to the noise level in the receiver front end, no further enhancement in this avenue will yield better performance. In today's receivers, atmospheric noise determines the noise floor, & not receiver components. Understand that I am speaking in practical, realisable, affordable terms here, so the purists take note please.
In amateur receivers, there is some degree of specmanship prevalent, where selectivity is concerned.
The author of the receiver article harped about buying the radios he mentioned with a complete set of crystal filters if possible, and he is 100% correct. Cascadable filters , that are sharp, have good passband
response & steep skirts, coupled with a decent passband tuning system , allow for the skirt width to be maintained considerably below the -60db point on the filter response curve, helping to reduce the effect
referred to as filter "blow-by". I don't want to get into a technical disertation on receiver design, so I will say that a number of good books on the subject are available from the usual sources.
The author of the article mentions the Ten-Tec Omni V as having very low "phase noise". The majority of amateur equipment today employs phase locked loop synthesizers for frequency generation, & all synthesizers have" frequency jitter" or "phase jitter" to a greater or lesser degree, as a function of their operation. These artifacts are referred to collectively as "phase noise". Several liabilities are inherent in the presence of phase noise. Again, only topically, the receiver can fail to detect a desired signal that is masked by the phase noise , usually present in the mixer stage, & also, those individual spurious frequencies that are present in the oscillator injection voltage, beat with unwanted signals present in the mixer signal input port, to produce a condition described as "reciprocal mixing". Simply stated, this means that extraneous signals (any signal you don't WANT to receive) present in the mixer RF input, are mixed with the spurious frequencies that are part of the synthesizer "phase noise", to produce an IF signal that has a number of unwanted components as well as the desired signal. The IF chain treats the IF passband as a wanted signal, & this pot-pourri of RF "garbage" propagates through the receiver.
In short, the "phase noise" essentially determines the minimum "single signal" threshold. Purists, I am trying to keep it simple, & absolute accuracy suffers, I know. Superior quality receivers minimise phase noise by various methods. Receiver dynamic range describes the range of signal levels over which the receiver can operate without exhibiting "blocking" (distortion of the received audio up to and including the momentary loss of audio...stuttering or burping) The better designs allow a much greater range of signal levels without operator intervention. Pages could be written regarding the technical features that permit a large dynamic range.
Reiver third order intercept point is yet another specification that separates the excellent from the mundane receiver. Amateur receivers in general fall short of military grade receivers in this area, by an uncomfortable margin. In crowded band conditions, with numerous high level signals, a receiver with superior 3rd order intercept specs will continue to deliver single signal reception , while the poorer receiver experiences loss of single signal reception caused by two strong, undesired signals, mixing in the receiver front end to produce a third signal on the frequency to which the receiver is tuned, overcoming the desired signal & replacing it as the received signal. Preselection, RF amplifier & mixer design all conspire to determine the third order intercept point.Yes Purists, I know the explanation would not satisfy the Radio Club of America...... A further consideration that sets the high end receiver apart from it's lesser cousins is the receiver audio chain. A great many low cost receivers, and some high end also, suffer from audio hiss, poor frequency response, terrible speakers, cross-over distortion in the Audio Ic etc., as well as lack of any provision to alter or taylor the audio response to suit the listener. All of the above constitute some of the differences that represent compromises in the receiver design, cost, implementation etc. After using a truly good receiver, it is hard to return to a bare bones unit.
For those who suffered through reading this , thank you. For the technically apt, I beg your indulgence for the less than complete explanations, & the concommittant inaccuracies required for the purpose of a simple explanation.
Regards to all, Brian VE6XX
 
High-End HF Transceiver Bargains  
by K5CFW on August 21, 2001 Mail this to a friend!
Thanks, VE6XX, for explaining a number of terms that we've all seen bandied about but that needed clarification.

About a month ago I found a used Omni-V with all the filters on e-bay. I'd been using a Kenwood TS-450S with moderate success... thought I needed to upgrade my antenna because I just wasn't making the contacts. As soon as I plugged in the Ten-Tec, it was as if all the bands suddenly opened up for the first time.

I feel like I've traded in my Ford Escort on a Mercedes 600... and the neat part is that my 10-year-old "Mercedes" works just as well as it did when it left the factory.

73, Cedric, K5CFW
 
RE: High-End HF Transceiver Bargains  
by N8FVJ on August 21, 2001 Mail this to a friend!
I also have an OMNI V. Great receiver and the audio based filter is superior to DSP in its present design. Nice to receive clean, crystal clear and undistorted audio.
 
RE: High-End HF Transceiver Bargains  
Anonymous post on August 21, 2001 Mail this to a friend!
The Escort/Mercedes comparison is perfect! Once you've driven even a 10 year old Mercedes, the shortcomings of your late model Escort will be painfully evident.

The exact same thing is true when you have the chance to compare the on-the-air performance of older, high performance HF radios to modern, mid-range radios that cost about the same.

 
High-End HF Transceiver Bargains  
by G3RZP on August 21, 2001 Mail this to a friend!
It is a mistake to separate intercept point, blocking, and reciprocal mixing, since they are all related. So a good intercept point is useless without good phase noise.

One parameter rarely mentioned in amateur receiver reviews is spurious responses. This may be because it is a lengthy process to measure, but with modern computer controlled test gear, it's not that hard. Some transceivers really suffer in this respect.
 
RE: High-End HF Transceiver Bargains  
by K3YD on August 21, 2001 Mail this to a friend!
I respect KG6AMW for asking the question which he has. Yes, the paper specs between average radios and "competition-grade" radios are similar. However, I would suggest that 'AMW try to compare two transceivers, side by side on the same antennas. The ability to "hear better" on some of the High-End transceivers should be obvious. Oh, they'll both sound OK on S9+ signals 40 Meter SSB at 10 AM on a Tuesday morning. But under more extreme conditions: a DX pilup, a crowded band, atmospheric fading, whatever, the "BETTER" radio will quickly prove it's worth!
 
High-End HF Transceiver Bargains  
by WB2WIK on August 21, 2001 Mail this to a friend!
Interesting thread of comments.

It is indeed difficult to compare rigs based on published test results, even when those tests and results are totally unbiased and by professional, independent test laboratories. The proof of the pudding is in the taste, and puddings having nearly identical ingredients, and resulting nutrients, calories and other properties can taste quite differently.

If I compare the TS440S to my TS850S on paper, I don't see a great deal of difference. However, when using the two side-by-side, connected to real antennas via a switch, the difference is staggering: The TS850S hears and works an amazing number of stations, using the same antenna and under identical conditions, that the TS440S simply cannot. You'd never guess that by reading the papers.

Likewise is the "transmit" comparison of my little Ten-Tec Scout 555 (50W PEP output power) vs. my IC-735 (100W PEP output power)...connecting them side-by-side to the same antenna via a switch, I can break through pileups in one call on the Ten-Tec that I cannot break through in ten calls with the Icom. The Scout runs 3dB less power. But it has such outstanding audio characteristics that it simply does a great deal more work with the power available.

We'd all be better off by trying and comparing rigs as much as we can, and select what is best suited for us and our particular operating environments (as well as within budget, hopefully!) -- what is best for me, or for you, today may not be best tomorrow.

73 de Steve WB2WIK/6
 
High-End HF Transceiver Bargains  
by N0SP on August 21, 2001 Mail this to a friend!
Hello Jim..
This is a good topic for those who want solid performance without having to purchase a brand new multi-thousand $$ radio... especially since some of those new pricey ones are not up to the basic receiver performance of a good 20 year old radio. Sad but true. Consider the popular Icom 756PRO.. a wonderful radio in many ways, but with a 3rd order (2-tone) dynamic range of 90db... about equal to the TS-50... not exactly a step forward in that aspect of performance.
I'm suprised you didn't mention one legendary performer in the "old radio" catagory... I'm referring to the mid-eighties generation Yaesu FT-102. The engineer who designed this thing had something special in mind.
First of all it incorporates a real permeability tuned oscillator, (not a noisy synthesizer), dedicated ½ mhz wide bandpass filters for each amateur band, PLUS a preselector to boot, (remember those?) the bandpass filters are mechanically switched, (no noisy diode switching) and a high-voltage front end to enhance dynamic range. All this added up to a very quiet receiver with a 3rd order intercept point of +19.5dbm! (ARRL Lab test) Also, it came stock from Yaesu with crystal filters and lots of spaces to add/cascade more filters. I've not seen another amateur receiver equal that +19.5dbm number.. the FT-1000 came close at +19.2 and I noticed the $6,000 Watkins Johnson professional receiver equaled it at +19.5. There may be some out there, but I've not run across any. Needless to say, it's impressive for an 18 year old design.
All this, by the way, comes at no penalty in sensitivity. After a careful alignment mine measured an MDS of -142dbm on 10 meters on a calibrated HP 8640B. (400hz CW filter)
The transmitter is no slouch either. It incorporated THREE 6146s in the final yielding around 160 watts output with 3rd order products around 10 db better than anything on the market at that time.. and has only been equaled in recent years by the expensive radios. When tuned for max output it would easily run over 200 watts but with a somewhat inferior 3rd order specification. The manual explains how to tune it correctly as opposed to the tune-for-max-output routine. Also the transmitter incorporates a microphone equalizer, true RF speech processor, and dual metering.
Unfortunately, Yaesu shipped these with inferior relays that ALWAYS began failing after a few hundred hours of use (some immediately!) so the radio got a bad rep early in it's career. Yaesu's replacement relays were not much better. Also, during that time period was the rush to solid-state "no tune" radios so marketing suffered a bit. It was, however, very popular in Europe because of their constant problems with very strong nearby shortwave signals that would reduce many "wide-band" solid state amateur transcievers of that day to a snowstorm of noise.
The Europeans addressed the relay problems themselves and the 102 remains very popular over there. Here in the U.S. a third party found the perfect replacement relays and has likely retrofitted most of the operating FT-102s in this country today. Mal, NC4L, does the relays then "blueprints" the receiver with an alignment that is probably better than factory, then provides you with a spec sheet on your particular unit.
I "discovered" this radio by accident when I lived on the coast and had tall vertical antennas 100 feet offshore in a saltwater bay. Nothing else handled the rock-crushing shortwave signals from nearby 41 and 19 meter SW bands as well as nearby MW broadcasters.. One very expensive Kenwood radio was completely useless on 160 meters. The FT-102, however, was completely unaware of the nearby MW broadcasters exept for a few mixes that were actually being transmitted by the stations.
On the used market they can be had for around $400 to $500..(often less) on a generic radio without the companion external synthesized VFO or other accessories. If, however, the radio has had the NC4L treatment and the seller knows what he has it will be closer to the $800 range on a clean unit. The best buy is to find one with unknown relay history and have it gone through so you're sure it's up to spec. It is not too expensive. The biggest hassle is shipping it to Florida. The external VFO is a nice add-on since it allows split operation and has memories, direct frequency entry, scanning, etc.
I now live in Colorado away from mega-strong SW signals... but I own 3 modern solid state radios, two with DSP, but the FT-102 is at center stage in the shack and is used when the going is getting rough. I like the convenience and automation of the new stuff. But unless I spring for a Mark-V (hail the return of the preselector) I'll likely stay with the FT-102.

73,
Dennis
NØSP
 
RE: High-End HF Transceiver Bargains  
Anonymous post on August 21, 2001 Mail this to a friend!
Shhh - don't tell anyone that the receiver in the Omni V is the same receiver as used in the Omni-VI/VI+
minus the DSP goodies. Hey, I told you to pipe down!
Don't believe it? Call Ten-Tec and ask them.
 
RE: High-End HF Transceiver Bargains  
Anonymous post on August 21, 2001 Mail this to a friend!
Shhh - don't tell anyone that the receiver in the Omni V is the same receiver as used in the Omni-VI/VI+

Yes, and it doesn't chirp as badly as the VI! Of course you don't have RIT on the V.
 
RE: High-End HF Transceiver Bargains  
Anonymous post on August 21, 2001 Mail this to a friend!
KG6AMW, several have attempted to answer your question, but I fear in their attempts to be complete, their answers took circuitous routes and may not have arrived at "the point". I beg for permission to make the attempt, and beg forgiveness as I will likely commit the same crime:


1) Sensitivity numbers for an HF rig are not a good way to compare radios. The noise levels on 160 - 10 meters are so high that ANY radio made today is sensitive enough.

2) Actual selectivity numbers are important, but when you're trying to receive weak signals on a crowded band, the most important factor about filters is your ability to select between many. Having four selectable bandwidths is better than having two. Having passband tuning or IF shift is yet another tool to help pull out that weak signal.

Also, "blow by" is never stated on the spec sheet. If a rig has poor filter blow-by, then there's more noise in the audio than if it didn't.

3) Another tool needed for good reception, especially on 80 and 160 meters, is an effective, and variable, noise blanker. There is no specificiation on a data sheet for "effectiveness" of a noise blanker. You have to trust other hams for their experiences.

4) I cannot emphasize this point enough: If you have a low-performance rig (which, by the way, does not automatically mean cheap - some low-cost rigs are pretty good, and some high cost ones are pretty poor), you may not realize it. Instead, you'll think the bands are noisy, or crowded, or propagation is poor.


I had in front of me the other day, three rigs. One a 15 year old early solid state design, another one a more modern solid state design, and the third one a 30 year old vacuum tube design.

The "worst" one was the 15 year old solid state design. If I connected that one to my dipole up 80 feet, I heard signals. I could tune to a weak signal, and fiddle with filters, IF shift, noise blanker, and pull the signal out of the band noise. When I put either the more recent solid state rig, or the older tube rig on the antenna, I didn't have to fiddle at all to hear that same signal!

Why? A combination of phase noise and receiver dynamic range issues on the "early" solid state radio left the impression that signals on the band were weaker than they really were, and that the band's noise levels were higher than they really were. Listening only to that one radio would not have told me that I was having receiver problems. It was only when I put a "better" radio on the same antenna that I realized what I was missing.

Additionally, when I had one of the "better" radios (the modern solid-state rig was superior to the tube rig in the variety and flexibility of filters; otherwise they performed similarly, despite the fact that the tube rig's receiver sensitivity was worse than anything made today - that's why I said you can pretty much ignore the sensitivity specs) on the antenna, I could hear some signals near the noise floor that, with proper filtering and noise blanker adjustments, I could hear perfectly. There was no combination of control settings that allowed me to hear those signals on the "poor" rig.

And if weak-signal DX isn't your cup o' tea, I also found that listening to SSB ragchews was far more pleasant on the "better" receivers. In this case, the phase noise of the "poor" receiver made all the SSB signals sound slightly muddier, and slightly less "out of the noise" than they really were. That would change a pleasant armchair-copy situation into one where I'd have to focus in order to really understand all that was being said.

So what should you look for in specs? Here's my take.

1) Best phase noise. Why? There's nothing you can do to fix it. When comparing rigs, make sure the phase noise specs are measured at the same frequency offset.

2) Most flexible filtering. Look for a combination of filter widths, IF shift and/or passband tuning. Rely heavily on the advice from other hams about how easy and flexible the filtering is.

3) Best and most flexible noise blanker. This won't be so important if you don't operate on 40, 80 and 160 meters. Rely on other hams for advice on this feature.

4) Receiver dynamic range. If you have difficulty with receiver overload, you can work with the receiver's attenuator, and maybe build some outboard filters to help with this issue. However, you cannot fix a close-in IMD problem.

Generally, the hardest spec to find a good receiver with is phase noise. I don't know of any radios manufactured in the last 15 years with good phase noise but poor IMD.

Best way to spend your time: Take the rig you already have to the home of a friend with something else. Compare them side-by-side in receiving tests. See what you can hear on one and not the other. Then compare the specs and see if you can figure out which spec "difference" caused the receiving difference.

Have fun!
 
High-End HF Transceiver Bargains  
by KG6AMW on August 22, 2001 Mail this to a friend!
Thanks for the information guys. I learned a few things.
 
RE: High-End HF Transceiver Bargains  
by VE6XX on August 22, 2001 Mail this to a friend!
Greetings once again: N0SP, thank you for your contribution, & I must agree whole-heartedly with your comments re the FT-102. The stated +19.5 dB 3rd order point is exceptional in an amateur receiver.
You may, or may not be aware that military grade HF receivers have 3rd order IP's of +25dB & greater, as a matter of course. I was most impressed with the comments from all who responded, & G3RZP is absolutely correct in his remarks re: phase noise vs 3rd order IP. "Anonymous", bless his heart, fleshed out my explanations, & did an admirable job of detailing, & going straight to the point. Thank you sir!
I don't understand why you choose to remain anonymous, but to each his own. The only time I take umbrage to anonymity, is with those folk who undertake a character assasination of others who post. Your post sir, was objective, offered constructive suggestions, & supplied valuable information, again, thank you. There is obviously a core of very knowlegeable folk who read & post here, & my offering , admittedly neither complete, nor a technical masterpiece, was directed at those amateurs, who may be less technicaly informed than others. The several posters who suggested that "numbers" comparisons are less than a perfect method of comparison, & that direct comparison on a side by side, same antenna basis, are, of course, correct. Thank you for bringing that suggestion to the fore.
It is a pleasure to read the different posts, all with positive suggestions, & informative tidbits.
Once again I have benefitted by exposure to the data here.
Regards & happy hamming, Brian, VE6XX
 
High-End HF Transceiver Bargains  
by G3RZP on August 22, 2001 Mail this to a friend!
N0SP praises the FT102. My father bought one in November 1983: he went SK in April 84, and I inherited it. The FT102 is fine but.........

The relay problem you can fix easily by a few careful cuts of the tracks on the PC board, and adding a few 22k resistors and blocking caps. This mod bleeds some DC through the relay conatcts and breaks down the oxide film. Mine is still on the original relays.

The real nasty in the 102 is if you are a CW DXer, especially on the low bands. The key clicks are beyond being fit for human consumption, but that is easily cured, and not by the recommended Yaesu mod. The crystal filter arrangement leaves a lot to be desired - CW wide is SSB bandwidth, CW narrow cascades all the filters. Easy to add a couple of diodes to arrange CW Wide to be a wide (800Hz) CW filter and CW Narrow a narrower filter. The real killer is a receiver spurious on 80 and 40, where a strong signal on 3500kHz or 7000kHz breaks through, getting weaker as the rig is tuned up the band. This is caused by the 6MHz signal used to mix the VFO down to 500kHz to 1MHz bleeding across the dual gate MOSFET mixer, and substituting an IC mixer cures that. Although it took me 17 hours of solid work one weekend to find and cure, and meant borrowing more test gear from work than my house was worth at the time! Another CW problem was a lazy crystal for the CW tx carrier generation. Seen this on a couple of 102's, and dropping the FET source bias resistor gives that extra bit of gain so you don't start calling 'RQ CQ CQ' because of the crystal taking time to start.

Some FT102's have a diode in series with the PA screen grid; this can lead, especially with older well worn tubes, to plate current runaway if/when you get negative screen current. By removing this diode and adding zener screen regulation and zener stabilisation of the bias and selecting 3 tubes with identical plate currents, that problem can be disposed off. It may well be found that the documentation and the actual rig don't match, too, when you get down to PC Board details. I've done a number of contests over the years, a lot of ragchewing and DXing, and 2 of the PA tubes are the originals: the other one is a better match to the two: it dates from 1971, and I used it at work in a commercial transmitter development.

Some 102's can be a bit unstable on 80 when operated into anything other than 50 ohm wideband load. A damping resistor and series cap in the PA grid fix this OK, and by choosing the correct point, it's only switched in on 80.

Why the FT102 has such a quiet local oscillator is a bit beyond me. There's nothing special about the VCO design, but it's really good. I haven't managed to mesure a +19.5dBm intercept, but only +16.5dBm. That is OK: I've not yet had the situation where IMD has been a limit (I have biggish antennas - 5 ele monobander on 20m and so on)

For anyone wanting a bit more on the relationship between phase noise and IMD, I did a paper at the RF Expo in 1986 entitled 'Phase Noise, Intermodulation and Dynamic Range in Receivers': that was published in the RF Expo digest by RF Design magazine. I can supply copies if anyone wants it: it's only available on paper though. There was also a paper for an IEE Symposium in London 'SYSTEM DEMANDS IN PERSONAL RADIO SERVICES': that I have in electronic form, and it quantifies the relationship between the phase noise limited dynamic range and the intermod limited dynamic range. ( my e-mail is peter.chadwick@ieee.org)

Getting extra crystal filters is not so easy. I got a narrow (1.8kHz) filter from International Radio at Dayton this year. George, W2VJN, warned me that he didn't have a mechanical drop in filter, but did have an electrical fit filter. That needed a couple of its ground pins clipping off, and two holes drilling in the PC Board to make it fit - no big deal. But fully kitting up a radio won't be cheap, although from a performance viewpoint, well worthwhile.

Some of the ICs aren't readily (or at least cheaply) available, but there's enough room in the 102 that it's not difficult to rebuild a bit of circuitry around what can be got. The likely biggest problem will be if the display goes, as those are made of unobtainium! Even then, it's not that hard to make something up, together with a new counter board.

Quite a few modern rigs with custom ASICs in will give maintenance problems in a few years, when the manufacturer no longer has any stock.......expensive junk piles will be the result!

So if you're looking for a high performance rig, and don't mind having a few nasties to contend with, or are happy with a soldering iron, the FT102 is good. I haven't found anything I'd change mine for, but as may be gathered, mine is hardly a stock 102......Of course, I'm also a bit mean - my home brew amplifier (pair of 4-250A) has a 6L6G screen regulator tube hat my father paid the equivalent of 25 cents for in 1936, and I want his money's worth out of that tube!

Unfortunately, at the present time, the '102 won't hear the last three countries I need - because they're not on. (Anyone going to KH7K, KP1 or P5?)

73

Peter G3RZP
 
RE: High-End HF Transceiver Bargains  
by N8FVJ on August 22, 2001 Mail this to a friend!
The late Doug DeMaw told me the FT-102 was overall the best receiver he ever owned. The reason I did not include it is the relay issue. Does Omron have heavy duty replacements?
 
RE: High-End HF Transceiver Bargains  
by G3RZP on August 23, 2001 Mail this to a friend!
The relay problem in the 102 is because the relay contacts get a very thin film of oxide on them. They don't 'wipe' so this film doesn't get broken, and acts as an insulator because the signal levels are so low. Using a resistor or two to the +24 volt line enables the oxide film to be broken down by the DC. This was a well known phenomena to telephone engineers back in the days of Strowger exchanges - there's history for you!

73

Peter G3RZP
 
High-End HF Transceiver Bargains  
by N1YRK on August 23, 2001 Mail this to a friend!
Thank all of you for information on this very interesting topic -- the best I have seen on eham.net for a while!

I recently acquired an Icom IC-751, and it is NICE. I'd like to hear people's comments on its receiver.
 
High-End HF Transceiver Bargains  
by KU3S on August 24, 2001 Mail this to a friend!
Really enjoyed reading everyone's responses. My vote(don't laugh) is the venerable Omni-C. simple, quiet, and selective and yes, crude...but I love it, Steve
 
High-End HF Transceiver Bargains  
by KD7KGX on August 25, 2001 Mail this to a friend!
I just picked up a Ten-Tec Omni VI/Option 1 and I think that it is the best high-end bargain around. I looked at the Omni V as well as several of the YaeComWood models, but none had the performance features.

These are going for $1600 or under (I paid well under that for mine), and they are an Omni VI+ without the capability of adding an extra 9Mhz IF filter.

If you price a like-new used IC746 or FT-920 on eBay, you'll find that the Omni VI/Opt1 can be purchased for about what they go for... and it's a much better radio!

What a great radio!
 
High-End HF Transceiver Bargains  
by W2RS on August 25, 2001 Mail this to a friend!
I second the comments of N0SP, G3RZP, et al about the FT-102. I've had one since 1984, and sent it to NC4L for refurbishment last year. Mal did a super job, restoring it to better-than-new performance. I operate mostly CW, and the FT-102 is still the best amateur CW receiver I've ever used.

When the radio was new, I installed the two 250 Hz Fox Tango CW filters instead of the stock Yaesu filters. I don't believe they're still being manufactured, but if you can find them and want the best selectivity in the CW-N position, get them.

I also have the FV-102DM digital VFO. Using it instead of the PTO degrades the receiver performance, but I find it a great convenience for general operating. However, in a pileup situation or any time I need the strong-signal handling capability of the '102, I switch the digital VFO out and go to the PTO. Under demanding conditions, the difference is amazing.

I also noticed the 3500/7000 kHz breakthrough problem that Peter described, and mentioned it to Mal when I sent him the radio. He fixed it straightaway.

About the only gripe I have about the FT-102 is poor audio fidelity in AM reception, the result of not having a true wideband IF position. For that, I switch in a Collins 75S-1, which has an IF bandwidth of about 8 kHz in the AM position, and a good-quality speaker.

The transmitter in the FT-102 sounds quite respectable in the AM position (with the AM/FM board installed, of course) if tuned up properly with about 25 W output.

As a relay-operated radio with vacuum-tube finals, the FT-102 is not well suited to today's new digital modes with their rapid-switching requirements. If you're into those, you'll probably want a solid-state rig.

Don't look for my FT-102 on eBay anytime in the foreseeable future. I plan to be using it for a long time to come.

73, Ray, W2RS
 
High-End HF Transceiver Bargains  
by KD6RWF on August 26, 2001 Mail this to a friend!
I HAVE AN FT-990, ATLAS 210, AND 210X. THE OBVIOUS DIFFERENCES ASIDE THE 990 IS FAR SUPERIOR TO THE ATLAS RADIOS. ON SSB THEY ARE NECK AND NECK. THAT'S MY INPUT FOR THE DAY.
73'S RICK
 
RE: High-End HF Transceiver Bargains  
by N0SP on August 27, 2001 Mail this to a friend!
I'd like to thank everyone for their informative comments that followed my posting on the FT-102. Jim, I don't know who makes the replacement relays that NC4L uses. I doubt he would hesitate sharing the information if asked.
Peter, you surely have put some time in to the 102 in your many years of owning one! With the exception of the well known relay issue, I've not had any of the problems you mentioned. Several good friends of mine have them and don't report those issues either. Two of them are nearly 100% CW ops and have not had key click problem. (or the lazy crystal syndrome) None of us are original owners so they may have been taken care of already, or maybe later production radios had some of those issues fixed at the factory. I purchased my FT-102 in 1989 with flat finals and bad relays. I replaced the tubes and they remain in the radio to this day. It got the NC4L relay treatment in 1990 and they have been trouble-free. It is very refreshing to hear the learned comments on this board regarding noise, recriprocal mixing, IMD, etc. These are lost on many hams since phase noise is not immediately recognizable as such. It simply sounds like bad propagation or a noisy band. Like Ray, W2RS, I also have the companion synthesized VFO and only use it when needed for split operation. On a quiet band I can't tell the difference, but I have been able to hear the phase noise degredation when pulling a weak signal out with nearby (>5kc) strong signals when using the synthesizer. It sure feels nice to be able to "turn off" a demon that negatively affects almost all modern radios.
Peter your "fix" for the relay problem was a dandy.. This is the first I've heard of it. You likely have the only operating FT-102 on the planet with original relays! There is no substitute for experience.
The type of hams that have taken to this radio seem to run the gamut... My friend Brian in Florida loves it's transmit audio quality, Luke in California is hooked on the velvet smooth CW tone using the International Radio filters and he especially appreciates the lack of "hisssss" in the headphones.. something which is present in the audio output stage of too many modern radios. And finally my friend Jim in Austin, TX. who uses it as in I.F. receiver for his weak signal microwave stuff because of the 102's quiet front end and high sensitivity on 10 meters... another area where too many new radios fall off a bit. I was initially attracted to if because of the bullet-proof front end. Some like the high power transmitter.
Jim, N8FVJ, mentioned that Doug DeMaw said the 102 had the best receiver he'd ever used... I'll add another name to the 102 hall of fame... When Riley Hollingsworth is probing the nether-regions of hamdom searching for those letharious characters among us what do you think he is using? A modern multi-thousand $$ feature-packed latest-greatest wonderbox from YaeComWood? Perhaps a $6,000 military receiver?
Nope, simply an FT-102.
73,
Dennis
NØSP
 
RE: High-End HF Transceiver Bargains  
by ZZZZ on August 28, 2001 Mail this to a friend!
Not to nitpick, but the FT-102 with its 3rd order intercept point of +19.5dbm is beaten by the Elecraft kit K2 which has a Ip3 of +21.6dbm as measured by the ARRL Lab (pre-amp off).

I guess sometimes high tech isn't the best way to go, eh?
 
RE: High-End HF Transceiver Bargains  
by W6WO on August 28, 2001 Mail this to a friend!
FYI I published a short article on this topic in the August edition of our club newsletter SHORT SKIP and invite you to view this at www.K6BJ.org

The Elecraft K2 RX is indeed hard to beat but to my knowledge no commercial HAM RX comes close to the best professional equipment. To approach the performance of a $25,000 RX it seems we must go to a home brew project such as that by John B Stephensen KD6OZH in QEX Magazine Mar/Apr 2000

I would like to hear from anyone who has built one to John's design or might contemplate doing so.
 
High-End HF Transceiver Bargains  
by G3RZP on August 29, 2001 Mail this to a friend!
Interesting that Ray and Dennis both comment about the phase noise of the FV102 external digital VFO. I thought it might just be me.....I've never got around to measuring it, but I've certainly noticed it.

You have to remember that Yaesu rigs seem to have more undocumented factory changes on them than most, for some reason: this certainly applies to the 102! Still, I like it.

One question that you really need to answer is:

How high an intercept point do I need?

With a +10dBm input intercept point (RF amp in), I have about an 8dB noise figure on 10 metres. That means the receiver noise floor is pretty well -134dBm. The external noise when switching from dummy load to antenna raises this to about -130dBm. So for two signals to give an intermod product equal to my noise floor, they each have to be at (to the nearest dB)-36dBm.

Now if we have the usual 50 microvolts = S9, these two signals need to be 37dB above S9. (Yes, I know the 'S' in 'S unit' stands for suspicious!) But it gives you an idea of the level of signals you need for the IMD to be a problem. For the signals to cause an IMD product to be equal to the noise, the sum of the receiver phase noise and the phase noise on the transmitter has got to be -128dBc/Hz at the particular offset, which may or may not be a problem. A discrete external spurious response at either of the frequencies causing the IMD needs to be rejected by 94dB.

So you can see why the IMD isn't the whole answer. Things are more complicated with multiple signals, where the number of 3rd order IM products of n signals becomes

[n*2(n-1)]/2

Just as white light is random phase and amplitude of all frequencies, so these many signals tends towards appearing like noise, but they need to be fairly big to be a problem, and when that's the case, the effects of phase noise can't be discounted.

On 7 MHz at night, the noise floor is higher - in my case, by around 12dB. So the RF amp is switched out and the IM products drop by some 30dB. The question really comes down to one of what's the biggest signals you are going to receive at your location, and what's the noise floor?

A multi-multi contest station will have a lot more problems in this respect than Joe with his vertical in the back yard. I haven't found an identifiable IMD problem with the FT102 even on 7MHz, with a full wave dipole (with open wire tuned feeders) at 60feet.

IMD and Phase noise are important parameters, but don't get too carried away and go insisting on performance that you may not need. A bit of analysis can be quite illuminating - even more so is a spectrum analyser!

73

Peter G3RZP

 
RE: High-End HF Transceiver Bargains  
by VK5NZ on October 19, 2001 Mail this to a friend!
Regarding old rigs..the noise blanker and receiver performance in my old IC 745 has made me keep it all these years. AS for an external DSP unit...the Clearspeech Base Unit is a real performer and has made my ancient radio more like a modern one. Even though I paid double the USA price it was still worth it. A number of other VK hams have bought the Clearspeech units. Just thought I'd mention DSP since it was raised here. With all due respects to Radio Shack and Timewave....forget it. !! 73 Bob..//
 
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