Cobra 2000 Taiwan model no RF out no mod no clock/counter

[357]

I just picked this up with the box and all but apon plugging it in, the clock/count digits and ch digits are lit dimly.
power on clock counter are mia. I was seeing mod on the mod meter at first but after some clacle pops from the speaker it stopped. nothing hot or warm
rx works fine
no power but I hear a carrier on another radio close by but thats it. on ssb the mod meter goes to the red then slowly drops all by itself
There is voltage on the bias tp and the bias trans is doing things on tx.

Just thought I'd see if anyone seen any of that before. gonna have to recap it I guess and do more checking. this clarifier mod has me worried

 

[357]

looks like they removed vr5. that red wire to the switch board has a cut trace dead end.
That mode switch has 8v not sure if its good enough but it seems to be.
finals are getting voltage and .7 volts on tx. guess pull them and test

 

[357]

final driver and pre driver 1973 all show good npn's 60, 20 70 hfe

 

[357]

all the voltages check out on the pre driv and final.....wth?
bias trans checks good at tx. maybe the mixer or c163 or c162?

 

[357]

8v on all 3 pins into L46
,3 out, not change on tx

 

[nomadradio]

Did you try an external DC supply feeding a DC power cord?

73

 

[357]

thanks Nomad,
no but I checked the volts are good 13.68v
I put the pre driv and final back in and on am while keyed, if I probe L46 output or C163 C162 it jumps up to 1 watt out on AM but the frequency shifts around, probably normal because I'm touching there but it wants to work.
could c163 or c162 be bad?

 

[357]

163 and 162 test good.
2pf and 46.8pf

 

[357]

ok I noticed on R111 I didnt have number "8" 6.48V so I replace C18 and modulation was back. I was yelling into the mic and I could hear myself then something else died and I lost bias on the final....I need a break.

 

[wp4electronics]

ok I noticed on R111 I didnt have number "8" 6.48V so I replace C18 and modulation was back. I was yelling into the mic and I could hear myself then something else died and I lost bias on the final....I need a break.

If you can hear on a different radio and the radio is “transmitting” but, no output power on the wattmeter the final is gone. By the way the transistor test “good”.

 

[357]

The final tested good... c1973, 2166, 1969 all were good and good HFE
I think the caps including the tantalum ones are toasted.
Radio looks brand new with the original box. shame.
I guess it sat too long

 

[wp4electronics]

The final tested good... c1973, 2166, 1969 all were good and good HFE
I think the caps including the tantalum ones are toasted.
Radio looks brand new with the original box. shame.
I guess it sat too long

The final tested good... c1973, 2166, 1969 all were good and good HFE
I think the caps including the tantalum ones are toasted.
Radio looks brand new with the original box. shame.
I guess it sat too long

The final tested good... c1973, 2166, 1969 all were good and good HFE
I think the caps including the tantalum ones are toasted.
Radio looks brand new with the original box. shame.
I guess it sat too long

Good luck and forget the advice.

 

[357]

OK well I recapped it, did all electrolitics and tantalum's.
Bingo bango she's up and running!

 

[357]

 

[357]