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Reviews For: ICOM IC-751A

Category: Transceivers: HF Amateur HF+6M+VHF+UHF models - non QRP <5W

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Review Summary For : ICOM IC-751A
Reviews: 114MSRP: 1395 (Net Price) during 1991
Description:
Medium size 100W HF rig. About 1986-93, no tuner.
Product is not in production
More Info: http.//www.icomamerica.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
001145
KC0FVV Rating: 2001-01-06
Good rig in many ways Time Owned: more than 12 months.
The 751A has one of the quietest receivers I've heard. I have 3 HF rigs, but I like this one the best, simply because I can leave it on for hours and not get "listening fatigue". Also has excellent dynamic range and a good sharp IF-based notch.

It tunes in 10hz steps, but sadly, it only displays to 100hz. It's not that big a deal, but since my other rigs show 10hz, I kinda miss it on the 751A.

I must respectfully disagree with several of the comments made in other reviews...

First, I STRONGLY disagree with the suggestion to install Inrad filters. DON'T do it! You'll never get the LSB/USB audio to sound right. The filters that Inrad says 'fit' the 751A are really poorly designed for this radio in my opinion.

In the first place, the 9mhz one doesn't even FIT! All you can do is dangle it down between the main board and front panel...really hokey!

But the real problem is this: At 500hz from the carrier, they're already 6db down; and at 200hz from carrier, they're 40db down! I.e., no lows at all left in your audio, xmit or rcv. "sounds like you're talking through a toilet-paper tube" is a typical comment. Basically, they're centered at the wrong frequency; too far from the carrier.

note: the filters I swept, and which are listed on Inrad website as being for 751A, are #110 & #314

If you want a chance at ease of balancing the audio response between USB/LSB and xmit/rcv, then I recommend you do NOT put narrow sideband filters in the 751A, especially the 9mhz IF. Look for a rig with stock filters, or even better, stock 455khz SSB filter and WIDE SSB 9mhz filter. The 2.8khz FL-70 can usually be found cheap on the used market.

Note: unlike many rigs, the 751A xmits through the same filters that you have selected for receive, i.e if 'filter' button is out, i.e. narrow is selected, your xmit audio will be narrow as well. (A simple mod is possible, using one CMOS chip, to force xmit to use the 2.6khz ceramic filter only).

Second, I don't understand why one of the reviews said it was 'built like a tank' or whatever. It's not. My front-panel is plastic, not die-cast aluminum; and the circuit boards are cheap consumer-grade paper-phenolic. No glass-epoxy in this rig. Overall construction quality however, is just fine. It's plenty robust, so long as you don't flex the boards badly, or drop it on the floor <g>.

Third, one writer spoke of his enjoyment of dual 500hz filters while using the "passband-tuning" (actually called IF-shift). I believe that the 751A DISABLES all 9 mhz filters whenever the IF-shift is turned on. I.e, I think he's actually only using ONE 500hz filter, in the 455khz IF. I know for sure that this is what happens on SSB anyway.

The Icom filters are great though, and one of the values of the 751A is that it includes a 500hz CW filter in both IF's, stock from the factory. And the IF-shift really does work sweet on this rig.

Note: the IF-shift on/off switch, and associated filter-disabling circuitry is NOT shown in the service manual! It's there though...just look for Q85 etc. off the left end of the 9mhz ssb filter... It was added between 751 and 751A, but schematic wasn't updated properly for 751A manual.

In fact, now that I think about it, I -am- sure that the 9mhz CW filter is also disabled with IF-shift on; because there are two complete switch circuits beside the 9mhz filters; Q85 et al for the SSB filter, and another identical ckt which can only be for the CW filter.

Fourth, one reviewer called it "a great $700-$800 bargain". I can't imagine paying that much for one. I see them all the time in the $500 range, so I guess that makes it a REALLY great bargain <grin>. I paid $450 for mine, with original manual. It was listed on the newsgroup rec.radio.swap, and at that time there were two others listed at similar prices.

DON'T get one with the internal power supply! It sounds real attractive, but the radio runs HOT HOT HOT with that internal supply. Without it, it's a nice reliable cool-running radio.

In summary, I love my 751A. It's really a great radio overall, with an excellent receiver and all the features I -need-.
WD4AC Rating: 2001-01-04
Holds it's own..... Time Owned: more than 12 months.
I purchased my original IC-751A in 1990. I sold it to a friend when I wanted to play computer. My friend recently offered an extremely generous trade opportunity and I brought the IC-751A back home. I had forgotten just how pleasant the 751A receive audio can be. The receiver is quite selective and compares favorably with my IC-746. I noticed the difference in response between USB and LSB, but I corrected the transmit response with a careful passband tuning alignment. I.E., transmit frequency response can be touched up with R337. Anyway, I should have had my head examined for selling the IC-751A in the first place. If it had a DDS like the newer radios, then you'd be hard pressed to beat the receiver. As is, it still hangs right in with the newer radios. Also, it doesn't need the owner manual handy to operate it effectively. That's a big plus..
WA4TLI Rating: 2001-01-01
Excellent Transceiver! Time Owned: more than 12 months.
I have had my IC751A since 1985. No problems at all. I had at the factory last year for a tune-up and battery replacement. I have carried it DX trips to St. Maarten, Madeira and Aruba. Worked CQWW in all these locations and worked flawlessly. I have used it in eight consective Field Days with no problems. Thousands of contest contacts in numerous contests and still going strong. I made the DXCC Honor Roll with this radio. I purchased an IC756PRO earlier this year. It is the only radio that I have found that is better that the IC751A.
VA7TT Rating: 2000-11-19
Great buy Time Owned: 6 to 12 months.
I purchased a 751A about a year ago. It was purchased to be a backup rig for my Omni V, and to be used on any dx holidays I might be going on in the future (has the built in power supply). The radio has been a very pleasant addition to the shack. It receives well, although in my ears, nowhere as good as the OMNI V under contest situations. I've been told that it sounds goods on transmit, both with the Heil headset (#5) and of course with the Icom hand mike. It is a lot quieter than two Icom 745s I owned before. To me, it's a great piece of equipment, and will probably become a classic piece of Icom equipment. If you are looking for a great backup rig, or even a main rig, the 751A should be considered. And NO, mine's not for sale.
KG5IF Rating: 2000-10-10
main rig for shack solid performeer Time Owned: N.A.
Ive had this rig since 1990. I bought it while I was in Scotland. Love it. Has all the features I want. Reciever and transmitter are solid. No complaints in the time I've owned it. Filtering on recieve is good. Pass band tuning is really great on it really squeaks out the last little bit of signal. If your looking for a main rig or a second rig and find one at a good price snatch it up its great.
KI9A Rating: 2000-08-07
solid old ICOM Time Owned: more than 12 months.
I have used all of the big boys during contest operations ( 1000D, MP, 781, 940, OMNI 6 ) & for the price on used market, the 751A is a fine performer. Using a rig under contest conditions with LOUD sigs ( and many of them !) stretches everything to the limit. The 751A rejects close sigs fine, about as well as my old 728 & about the same as my 746. If there is a downside, it needs a UX-14 to connect to the CT-17 for computer control-& those are SCARCE!
KG8ZH Rating: 2000-07-05
Excellent Rig Time Owned: 3 to 6 months.
When my Yaesu rig bit the dust on me, I found myself in the market for another rig to replace it.
The Yaesu went down at a bad time. Money was tight and I was looking for a good deal on an H.F. rig. A local ham told me he had a IC-751A for sale and offered me a good deal on it. I was not familiar with the 751A, but told him I would look at it. He let me try the rig in my shack for a couple weeks to make up my mind. I quickly fell in love with this rig. Recieve is very hot on it, and the built in keyer has excellent keying action. QSK is great and keying is very clean. It works better than anything I ever used on cw. The 751A is very feature packed and competitive even against modern rigs. With built in VOX, Keyer, Pre-Amp/Att, Notch filter, IF shift, General Coverage recieve, Dual VFO's, RIT/XIT , 5-100w variable power output and the option of dual filters. About the only thing missing is an autotuner, but this is no problem. I use an Kenwood autotuner that works great with the Icom. Another thing I like is the size. It's big, but not so big that you'll have trouble finding room for it. It also has man sized knobs, so if your trying to push a button, you won't accidently hit three buttons because you can't get your fingers between them.
If you're looking for a used H.F. rig and run across a 751A, grab it. You won't be sorry. Recently, I ran across the guy who sold me the 751A and he was sorry he sold it and wanted to buy it back. I said sorry, but this one is here to stay.

P.S. I don't miss my Yaesu
N.A. Rating: 2000-04-02
IC751 owned since 1990 and I will not sell it! Time Owned: unknown months.
I bought second hand my IC751 (not the 751A) in Scotland. It had a faulty pre-driver(TX). I believe it is one of the best RTX produced. I am one of those that tried to build his own RTX but due to "not available time" had to go "black boxes". I had applied a few mods to it but recently I modified the third receiver mixer (9.01 MHz to 455 kHz). This is a Dual Gate Mosfet. I wanted to experiment with the H-mode mixer (G3SBI)using the Fast Bus Switches as my own idea (See various reports on Technical Topics, by G3VA (RadCom - RSGB). Not being able to get hold of some FST3125, I decided to experiment the same circuit using the 74HC4066 and its associated driver 74HC86. The change was not too difficult. Only three cuts on the Main PCB. I had to add a JFET buffer to adapt the 2nd IF output amplifier (9.01 MHz) to the H-mode mixer. I used the old DG MOSFET as post-mixer amplifier to drive the 455 kHz xtal filters.
I was shocked by the results. I discovered a very high drop of RX noise. Now, when I switch from no antenna (no termination)to antenna (a simple I7SWX windom 10 to 40 meters installed on a small terrace and held up by 2 fishing fiber rods)I do get the real bands noise, not the front end one. On 7 MHz, in Europe the Broadcasts are very strong, before I had my Smeter that was always around S6-8, now it goes to zero index. I have been listening to W stations for the first time. I was even able to work 10 during a recent SSB contest. Well, I was so exited I could not sleep the first night, hi! I was able to arrange, thanks to Maurice F5NRZ, a test to measure the IP3. We used an HP and a Schlungberger signal generators, a combiner good to GHz, a Rhode & SChwarz attenuator (GHz) and no low-pass or band-pass filters. Test was done at 14.200 & 14.220 at -10 dBm. We followed KI6QP method (QEX April 1995). The IP3 values detected are as following:
IC751 without preamplifier = +20dBm
with rf preamplifier = +15dBm
without pre-amp and
attenuator inserted = +29dBm.
The attenuator value is -20dB. To measure this value we had to increase both generators signal to 0dBm. Probably this value takes into account some IP3 generated before the transceiver. This is an important change. Certainly, using the FST 3125 I could have at least +3 to +5dBm higher IP3 figures. Now, as soon as possible, I will apply the mod to the 1st mixer (HF to 70 MHz). This time I will use the FST3125 (the mixer is ready). For people interested on the improvement of a transceiver or RX, the H-mode mixer is recommended, even using the 74HC4066 (for the last mixer). A more detailed report and circuit diagram should appear on Technical Topics. Complete technical article is expected to be published, as soon as completed, on Italian, US, Franch and possibly other Ham Radio Magazines. This will report, also, possible suggested mods to other equipment.
I am enjoying my IC751 like never before. The signals I do listen on all bands, with preamp on, are there when I switch it off and also with the attenuator inserted.I am able to copy low signals in presence of strong nearby stations.
Sorry but I will not sell it!
73
Gian
VE2JL Rating: 2000-01-16
751A ---A KEEPER !!! Time Owned: unknown months.
After 10 Years, never a problem and still competitive. No reason to trade for DSP rig as I never try to QSO with weak signals except in contests. The memory battery scare has always worried me but there are several options WILCO and the board from the Italian ham. Hasn't been back to ICOM yet. INRAD filters are good investment. Has enough knobs to play with without getting confused. Enjoy it ! 73
N5HG Rating: 1999-12-28
I have one too :) Time Owned: unknown months.
Not much more I can add further to what has been said. The 751A has been an exceptional radio over the years I've used it. Excellent receiver, and frankly, other than the 781, I can't think of another Icom I'd rather have. As another poster said, the ICOM 751-A is without question one of the best radio(s) out there on the used market.