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Galaxy melaka- EPT-360014B

NO RX on AM , period, NO RX Signal and No RX audio
SSB RX Good
AM TX dead key wide open 10+ watts dead key with no forward
and no modulation
SSB Tx also seems alittle low, But it does have TX Audio on SSB.
But it only has about 5 or 6 watts peak output on SSB.
Audio at P.A. Is good.
So far i have changed TR-51.TR-50,TR-49,TR-52,,C-190,C193
With all new parts..Also R-243 Beside the AM Mod Amp gets
extremely HOT, only just a few seconds after powering up radio.
I have checked the diodes around the Mod Amp,they check good.
Have not changed R-243 Yet,,But i checked it in circuit and it seems
to be about right..What else could be shorted here i am missing.
Thanks for any ideas..

Just a quick idea, did u remove the metering jumper and see if the excessive current draw is gone?

Yes i removed the mirror board,disconnecting both finals and driver
Excessive current draw still there.R-243 Still gets extremely HOT.

It would be a good idea to test the pass regulator with a load.
What is the drop across the pass regulator?

James.

The voltage at mirror board is 14.0 v.d.c.
I traced R-243 to the ssb shunt switch.So i decided to try
and remove ssb shunt TR-52 and then retry unit.
Removing TR-52 ssb shunt regained my AM RX.
But still no AM TX Audio,Dead key still wide open.
I am going to remove T-1 and check it.
And check the rest of the caps on AM Mod amp line.
Any other ideas will be appreciated..Thanks for your help
so far.

If the pass regulator is drawing a lot of current you will not be able to modulate it.
That why I ask you what the drop was across the pass regulator.
You can try in injecting a 1khz tone in to the base of tr49 and or tr50 while in the AM TX mode.
Is tr54 short if so this will stop your AM audio dead but will work on FM.

If you do not have a 1khz tone generator have a look at my good old mate Rick stuff on cbtricks www.cbtricks.com/members/index.htm there is a easy to build Two Tone Test Generator.

James.

Just to let everyone know, I got this radio back going.
The problem was i got a bad batch of new parts from
h and y.. I changed these parts with some old stock i had
and that did the trick..The moral to that story is, Dont ever
assume just because they are new parts that they are good.
I just bought almost 200.00 worth of parts from these people.
And from the way it looks, probably half of the parts are crap.

Was TR51 low DC gain?

Yes, it did check low on the transistor checker.
TR-52 SSB Shunt was shorted, so i think hat is what
took out the new MOD Amp TR-51 2SB754. When the fault
was on, the voltage across all three pins of TR-51 was 13.0+ v.d.c
In turn the radio was dead keying 10+ watts but had no forward and
no AM Tx Audio.Also with the fault on, and the shorted ssb shunt
in series, AM RX Was cut off. And Resistor R-243 Was so hot you
could not touch it.