I would like an opinion on TL-922A.

[Robalo]

I just got a TL-922A and before booting it up I would like to know if any of you happen to see anything wrong with it. I’ll attach some photos below. 73’s

 

[Dr_DX]

Just my .02

I would check the transformer that burned. Check the bandswitch contacts, especially on 10m. The resistors in the VHF suppression circuit on the Tubes look like they have been very hot. You didn't say how old the amp was. If the HV caps are old, I would change them and any other electrolytic. I would also bring it up on a Variac.

 

[BJ radionut]

Kenwood TL-922 HAM RADIO PA facts , modifications and key facts in the modern world

TL922 Amplfier TL-922 Kenwood Modifications

mods and modifications for kenwood TL922 stability and life

www.w8ji.com

Kenwood TL-922/A | Product categories | Harbach Electronics

harbachelectronics.com

http://w4lac.net/files/pdf/Kenwood%20TL-922%20Modifications%20Part%203.pdf

The NEWEST 922A's are 30+ years old... if it has 10m on the band switch (?) years old... These were made during the Hybrid Transceiver Kenwood Era.
The band switch is the weak link, the contacts were too small (Close together)
Nice amps really. They don't like DIGGI or AM Mode unless operated about 6-700 watt PEP OUTPUT Max.
SSB-15/10m best operated about 900 watts PEP OUTPUT, the rest of the bands around 1200w...
Similar to L4B output. Both were sold as near legal limit amplifiers.

 

[BJ radionut]

Robalo: Most of these links you will notice are geared toward the TL922...This is due to fact that the 922A's were produced after the FCC Amplifier Rules change. This is when 10m was removed from most production amplifiers.
We all know how well that rule worked out!
So hence pretty much all info on the 922 version applies to 922A as there were only minor changes to the general production of these units other than the Band Switch/Tank Coil changes.
I owned one years ago, as a "tabletop kilowatt" they were nice. The KWD TL922 actually had a "little" more output than the Drake L4B as the Plate Voltage (B+) was a little stronger than the Drake.
They, however, were heavy, and were known as big heat generators as to have all in one box (PS and RF deck) pretty much same as the SB220/1 package. I always like to tell those that operated these, an extra fan on top of case "pulling" air off the top of the tubes was a good idea.
GL
ALL the Best
Gary

 

[Robalo]

1st test turn on with 120v the picture one have 2.2Kv on CW, 2nd picture 3.2 Kv on SSB

 

[Shockwave]

The parasitic suppressors on the tube anodes, are far from stock. The original carbon resistors are hard to find today.

 

[Robalo]

Update the amp is up and running now on CW with 70 watts dk it outputs 600 watts dk.(10m-11m) test on dummy load.
SSB WITH 70 WATTS it does 1400-1600 watts pep. The amps are also running on 120 volts. I am happy with that, thank you all for the help.

 

[Robalo]

the relay now is stock on RX, and also the parasitic suppressors on the tube anodes getting to hot, how can i fix that.

 

[BJ radionut]

the relay now is stock on RX (Stuck?)

If you're sure the "cable or method used to key amp is working correctly. Then I would lift the coil wires for relay, add ex power source and does relay work?
Of course, all safety FIRST...Amp unplugged/discharged etc. before testing.
I think Tom/W8JI has recommendations for choke replacement. Hopefully those are getting hot due to the way they have been redone and have not been "rigged" because the amp is oscillating on its own.
Watch that DK on AM ... 600 watts IMHO way to strong (more like 350 should be it) again IMHO
Get that amp on 240 volts.
GL
Be here if I can help
All the Best
Gary

 

[BJ radionut]

http://w4lac.net/files/pdf/Kenwood%20TL-922%20Modifications%20Part%203.pdf

Scroll down to last page for Choke details.

TL922 Amplfier TL-922 Kenwood Modifications

mods and modifications for kenwood TL922 stability and life

www.w8ji.com

 

[Robalo]

Only ssb been used it on dummy load, for testing thank you

 

[Robalo]

Getting ready to make The parasitic suppressors

 

[Robalo]

Getting ready

 

[Robalo]

I was testing the AMPs on the dummy load with five watts only on CW and the parasitic suppressors on the tube anodes have burnt out again. Any clue as to what I should check or can do so fix this issue? The tubes are still functioning properly.

 

[Robalo]

Getting better