G.E. Superbase 3-5875A no output

[maverickman]

I have a Superbase that has no output power in any mode but modulation does show on the meter in AM mode only.
Receives in all modes perfectly.
So I'm not a novice by any stretch but this has stumped me so I figured I'd seek help in order to be pointed in the right direction.

What I've done so far:
1. Verified mic is working
2. Cleaned all switches and connections (DeoxIT)
3. Checked all white board connectors
4. Checked all grounds
5. Checked all fuses
6. Went over every solder joint on the transmit board
7. Plugged external speaker into PA (nothing)
8. Replaced finals but the originals checked out fine

I read somewhere it could be the AM Regulator?
I don't know the part number or location of it?

Any help would be greatly appreciated.

 

[loosecannon]

you need to re-cap that radio, it is too old to be reliable.
LC

 

[Yeti Communications Ltd]

AVR (automatic voltage regulator) transistor is Q126 (2sd712) can use a TIP31 in its place
the ge super base uses a modulation transformer not transistor for modulation
the avr is worth checking as its the main voltage reg for the radio
diagrams here http://www.cbtricks.com/radios/general_electric/3_5875a/index.htm
as LC said recap it ...but that goes without saying
check to see if you have bias voltage also
this board is prone for leaking caps taking out the tracks that run under them check continuity of those tracks once you have lifted the cap off them ..the glue holding down the main electro caps on these boards in the twin board pll02a radios also eats the pcb tracks under and around them (the caps)

good luck!

 

[BBB]

My reliable G.E. Superbase is a HELP! 3-5908A radio into a 2x4

 

[StrangeBrew]

My reliable G.E. Superbase is a HELP! 3-5908A radio into a 2x4

Bet that thing really locks down channel nine.




I've always wondered about those things. They're cheap and always available on the used market, if they perform anything like the older GE mobiles they would be pretty close to the perfect slip seat rig. You'll have to start a new thread and give us a review on that thing some time.

 

[maverickman]

AVR (automatic voltage regulator) transistor is Q126 (2sd712) can use a TIP31 in its place
the ge super base uses a modulation transformer not transistor for modulation
the avr is worth checking as its the main voltage reg for the radio
diagrams here http://www.cbtricks.com/radios/general_electric/3_5875a/index.htm
as LC said recap it ...but that goes without saying
check to see if you have bias voltage also
this board is prone for leaking caps taking out the tracks that run under them check continuity of those tracks once you have lifted the cap off them ..the glue holding down the main electro caps on these boards in the twin board pll02a radios also eats the pcb tracks under and around them (the caps)

good luck!

Thanks for info, I'm gonna take a look at the AVR.


@Yeti Communications Ltd:
Just one correction in case someone needs this info in the future and for some reason the schematic isn't available.... the AVR (2sd712) is Q216 not Q126 .



Thanks again for the info and I'll try and remember to post back here if that was the issue or not.

 

[Yeti Communications Ltd]

Thanks for info, I'm gonna take a look at the AVR.


@Yeti Communications Ltd:
Just one correction in case someone needs this info in the future and for some reason the schematic isn't available.... the AVR (2sd712) is Q216 not Q126 .



Thanks again for the info and I'll try and remember to post back here if that was the issue or not.

typos are forgiven here right?

they are gif files so paint will open them ..i have converted to jpeg for you