I have an older style 2950 and I recently had a problem with it warbling on SSB and checked the power cord and the power cord I was using was on only like 20 awg! I replaced that cord with the proper cord 16awg and now I don't have that problem. Running it on an Astron RS-12A 9 amp cont. 12 amp peak supply.



Anyhow, I now want to do some modifications to this thing and I came across a few and wanted feedback if anyone else has done these things to see if they got the claimed results before I got the parts and spend hours doing these.



For more stability and better modulation:

Change Q51 from 2SB754 to 2SB688 or even better 2SB817



For better sound quality

Change Q53 to 2SA473



To improve low power swing:

Change R178 to a 3k ohm.

Change R194 (10k ohm) with 4.7k.

Change R281 (4.7k ohm) with 10k.



For more output on AM and SSB:

Parallel C270 with a 470pF ceramic disc capacitor.



For better receive:

Change D34 and D35 from 1N60s to ECG583



For even more ouput:

change finals from 2SC2312 to MRF 477 or MRF 497



How much retuning is involved in these. Am I going to have to retune the output? Are any of these mods going to cause me to be off frequency without retuning? I don't have a scope or freq probe to retune it with.
















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Bump

From my experience if you change any component that changes in Value there is some retuning involved i would suggest finding someone with the right equipment to do the mods and retune it do you have a local tech?