Ray,

I have one of Helge's first prototype boards in my dog pile collection for that engineering bulletin along with his wavetex generator, scope, freq counter and other equipment. When I left Motorola RF back in1998 I was given some of his old engineering  boards and bags of development transistors so I may have some original dated but still fine Motorola 454's in bag at one of my qth's.

Does your amp use MaCom devices or original dated Motorola parts?

What I found when the transition from Motorola to MaCom came about was the MaCom devices have higher gain and depending on the collector voltage and the load Z there were some spurs visible during load pull test that are dependant on the input voltage and the temperature of the heatsink.

Operation above 13 volts was stable for my board with original Motorola devices but spurious using MaCom MRF454'S during some of my load pull tests.

My fix was to parallel 2x 10 ohm resistors across the original R5 and R6 locations in place of digging deeper and adding C-B feedback networks.

Since iv'e now moved up to freescales HV6 and HV8 devices I never really sat down to play anymore with any of my older bipolar amps since about the 2000 to 2001 timeframe.

But I also agree with others that should also check your grounding and enclosures if the input resistor changes don't resolve it.

Mike
WB8VLC
Prescott,AZ. Or Salem, Ore.


Edited to fix frigging android auto spelling BS and other android annoyances.

I have been testing Phillips and Cree led bulbs and so far everyone tested has wiped out the upper portion of HF, 40 to 170 MHz and to a lesser degree 180 to 359 MHz. 

My test started when I discovered that avionics receivers being tested in my professional Lindgren screen room were off in sensitivity by 30 DB or more.

Further investigation showed that my facilities engineer installed some Phillips led bulbs and then replaced the Phillips with Cree led bulbs that were just as noisy, my final solution was to go back to incandescents.

What worries me is the excessive noise in the 108 to 137 MHz range, A's I said it degraded the sensitivity on a commercial aviation NAv receiver between 108-118 mhz and a similar transceivers receiver between 118- 137MHz.

It appears to be the switcher/ converter creating broadband noise.

We need to worry just as much about led lighting as we do the recent FCC bpl ruling, both are destined to create serious problems for hams and aviation users.

pros about encryption: Because I don't want the local deputy transmitting mine or anyone elses social security number over their traffic channel in the clear.

cons about encryption: On the other hand I like to be able to listen to our local dispatch channel to find out about any accidents so I can plan an alternate route around town.

You can't have everything and I know some departments have encrypted sensitive information while others like simple dispatch comms are in the clear.

 Like others have mentioned Lindsey Blanton has screwed up public safety listening for all of us what with him streaming of everything and anything he can get away with.

Fortunately he's smart enough not to stream things like CBP and other FED comms, not that he can since they are all mostly encrypted anyway and this is probably the only reason he doesn't have any FED comms streaming.

http://www.randl.com/shop/catalog/product_info.php?cPath=1340&products_id=70202

 I would also check out the new Innova line of antennas, some are going for a really nice price such as the 3 L above.

RnL also has some nicely priced Hy-gain antennas, such as the 5 L below, but I'm not sure if Hy-Gain is owned by MFJ now which would raise a quality flag issue for me.

http://www.randl.com/shop/catalog/product_info.php?cPath=1340&products_id=33042

There used to be a couple of tokyo-Hy-power ssb handhelds back in the 80's and 90's,

the THP  Ht-750, 6, 15 and 40 meter model was one that I remember.

Items included in the standard package which I would pay more for than what is presently available on the market today.
Include everything already mentioned plus:
1. An acurate battery gauge.
2. A clock.
3. A drop in charger that conditions the battery pack if it is non lithium instead of crappy wall chargers.
4. A alkaline battery pack included.
5. A keypad that is backlit.
6. A protective radio case.
7. LCD Display backlight adjustment.
8. RF sensed/switched antenna port for an optional convertacom/drop in mobile charger.
9. Touchscreen control of some features.
10. Individual squelch and volume controls not controled by the touchscreen.

I use this model transmitter for my HF/6meter radios to a remote receive only headset or speaker and also as a BT audio streamer for all of my HT's as a listen only device and it works fine:

http://www.newegg.com/Product/Product.aspx?Item=9SIA0WP0902198

 I made up a USB 5 volt DC supply to keep mine charged/powered all the time when hooked to my base radios.


 You don't need to use the NewEgg product as just about any model of audio streamer will work fine.


Mike


 

I use one on the upper HF bands, one on my 10 meter FM remote base and another on my 6 meter FM remote base.

 I modified my lower HF section to work on 6 meters and added in the missing noise path pre-amps on one 1025, with these changes it works fine to null out the various noise sources that I have at my radio location.

 However; if you do get one then I would suggest to purchase the MFJ-1026 which has a switchable dual section preamp for the noise antenna path, and I suggest this model because the MFJ-1025 does not have enough gain in the noise path to work properly.

 Also if you do purchase the 1026 model  don't even waste the time to use the internal whip antenna port as it does not have enough gain to null noise out, the only way to go is to use the external noise antenna port.

 Also plan on testing out several different noise antenna locations and different styles of null antennas.

 I have used both wires and verticals and each one works fine depending on the noise that I am trying to null out.

Also careful and slow tuning of the controls along with trying all settings is the only way to find a good null setting.

FIA,

 Your shipping time really doesn't sound to unreasonable but I can understand being upset especially if you expected it on some specific date.

 I ordered a solder iron for my son from PARTS EXPRESS for Christmas around the first of December and was informed that it would ship late on Dec 7th but still it never arrived by the 14th.

It was only after receiving an e-mail to rate them that I mentioned never receiving half of my order only to be told that it will ship around the 26th of January 2013.

 This is even way to late for my sons X-mas let alone even his B-day, just be happy that you receive it within one week and not 2 months.

In the mean time I had to order a new Iron but this time from Amazon.com which fortunately is supposed to arrive tuesday.

Next time for me it's either HRO or Amazon as I have never been let down by either but just this one time I was looking for that good deal that was too good to be true and it just about messed me up.


 However on a good note since it has been snowing the past day the 3 Parts express catalogs have been put to good use, they work just fine starting my fireplace up.

I use 220 daily here in Northern Oregon and have come to like it, it has similar propagation to 2 meters with a similarity to 440 where the signal gets out of vehicles and structures better than 2 meters does.

 Prior to using 220MHz I had a remote base on 2 meters, this was before a coordinator suggested that I should move up to 220 MHz, using the same style and gain antenna and same power level on 2Meters as I now use on 220 MHz and I did not note any reduced range between the 2 bands.

I have a 220 remote base linked to 10 meter and 6 meter FM using a converted DB products DB-222 folded dipole on 220MHz which is the best antenna that i have found to work on 220 MHz.

 My remote base uses a converted Motorola Maxtrac as the main 220 transceiver with a GE Orion converted to 220 MHz in my 4 X 4 and a GE MPA handheld also converted to 220 for use around town.

 As you can see I like to use all commercial radios on my end especially since they were all free along with the spare DB-222 VHF folded dipole antenna.

Prior to moving to Oregon I never really used 220 but since all the VHF and UHF remote base frequencies are taken up here it was 220 or 900 Mhz and 220 works much better with all the tall trees in this country.


 I too am looking at the TH-F6A  just so I don't need to carry so many commercial VHF and UHF handheld radios around.

Have you thought about opening up a Skeet shooting range?

 Imagine the possibilities if you could just come up with a Skeet launcher that could toss an FT2000 a couple of hundred feet in the air.

 You can have people bring in all their crap such as, SteppIR antennas that don't tune, Alinco radios that sound like crap, Kenwood, Yaesu and Icom VHF/UHF radios that blow the finals for no good reason, the junk Rotator that stops working during the only 6 meter opening in months, the Pyramid power supply that suddenly started putting out 24 volts to a 13.5 volt rig, Dell PC's  and don't even get me started on the cheap crappy Chinese radios.

 Just think of the assortment of electronic junk being produced these days, junk that people would bring to your Skeet range to blow away.

 I would pay any reasonable fee to have someone set up all or any of the above mentioned crap in a simulated Iraqi Village and then let me run around with a weapon of my choice and shoot all of the above mentioned junk to pieces.

 I feel better now, I feel like tossing my crappy unused 220 radio out in the mud and rain, now if only there was a shooting range close by.

I have placed phone, ipad and radio chargers in my checked baggage in the past and had them mysterious leave my bags when flying from Phoenix Sky Harbor airport so never again for me.

 I forgot to mention that also I set my VHF and dual band radios to a weather channel also just in case someone turns one on.

 And last I also forgot to mention about the plastic bag for spare batteries and radios, I ave been doing this lately and it does speed up the Bin checks by TSA as opposed to having things loose.

I have never been asked to turn on any radios or GPS units.

I usually take 1 or 2 XTS5000' s an MT1000LB and an ICOM T7H routinely between Phoenix and Portland, Phoenix and Minneapolis and Phoenix and Detroit and I have never been asked to turn any of them on.

I have never had a problem with the batteries either and while waiting for others to board, while still on the ground, I have had my radio on listening mode using a bluetooth headset and never had a problem with the flight crew.

 Once the seat belt sign is on and were leaving the gate I turn everything off and put it away in my underseat bag until we land.

 I always have a copy of my license, a QST and all operating manuals in plain sight with my radios and I keep everything in my carry on bag.

When going through security I pull all radios and chargers out and place them into a bin for closer inspection.

This is my preference to carry all in my carry on bag because Phoenix is notorious for having radio and cell phone chargers stolen from checked baggage so I carry my radios and chargers in my carry on bag.

 In 10 years of flying I have only had one TSA screener comment and it was in in Portland Oregon and he said nice radios.

Or the bandpass filter in the 225 to 384MHz band is rolling off attenuating the signal in this portion of the radios coverage.

Have you checked sensitivity at say 225, 250, 400 and 450 MHz in any mode?

I'm sure we will have a chinese version soon anyway (treenkies) so I wouldn't worry about it, after all there is always Beer and Pizza.