modulation on a.m. + ssb.

[KC8PQN]

I have a kenwood TS440s and I hear that it sounds bad or has very low audio on A.M. and when you bring the mod. up just enough to have louder audio it breaks up. I know that the finals are not quite %100. I cannot figure why the audio is low. Too low. if anyone can help. I allways hear that its a good side band radio. though we all know that ssb. allready has its difficultys with audio. so its all a bad radio if I dont figure this stuff out. thank you, if anyone knows what might be a fix for that .. I would love to know --*** ***-- # #Dan (KC8PQN)

[w8jas]

what band??

Am is only going to be 40% PEP.

Original mic?

What are you using as a audio singal source when you test?

[VE1IDX]

What do you mean by "I know that the finals are not quite %100." The finals are solidstate,either they work or they don't.It's not like a tube rig where the finals CAN be somewhat less than 100%.If there is an issue with the finals then I suspect that is where the audio problem is.

[ka5piu]

Hello.

The Kenwood TS-430 and TS-440 are not noted for being good AM rigs, in fact they are marginal.
What I do is have an amp that I modulate by way of swinging choke and audio amplifier.
The TS-430 in my case is set for CW at around 50 watts for a real ham amp and placed in transverter mode to run 5 watts for a converted texas star.
Note that the texas star is run well within its ratings and at the output is a low pass filter.
At one point I had a swinging choke across the finals of the TS-430 proper, but this was not a very clean signal.

[k6jpd]

had a similar problem (only on ssb) tracked it down to VCO-5 go here and look around http://www.ham.dmz.ro/kenwood/ts-440s-circuit-improvements.php good luck