Uniden PC 76XL
 

"radiosrfun" wrote in message news:...
Have a Uniden PC 76XL CB set which is emitting an on frequency carrier -
albeit damned near dead - to a near by receiver set to the same channel.
There is no modulation going through it at all ***. There was a partial
leg sticking out of the D8 spot - it was either pulled or fell apart - not
sure which.

*** When I have an External Speaker hooked up via the jack, I seem to get
Modulation through IT and hear it on the near by receiver at the same
time - otherwise I get no modulation at all. The RF meter still isn't
moving in either case. The PA function seems to operate ok, as does all
other functions.

I don't have a schematic for this thing - and was wondering if anyone had
a copy of it they could scan or whatever. The set doesn't "appear" to have
been modified other than the D8 ("possibly" cut).

OH and the finals are good.

Any ideas anyone can lend on the cure of this, would be good too. Never
seen this issue before. I HATE not having a schematic. That is the biggest
pain in the ass I can think of in this field.

TIA and MERRY CHRISTMAS


OK, I did some research........

First off, "I" am not into "mods" of CBs - so I wasn't sure if this diode
was a part of any Modulation mod. In my research, I found - at least in the
few sites I went to - that the D8 wasn't a part of any mod. So - maybe it
was pulled instead of the D11 - which is stated to be pulled. I'll replace
that first and go from there. I did manage to find the other mod info which
I'm going to check as well - to see if any other tricks await.

I also managed to scrounge up the schematic too - so I should be good to go.
We shall see!

Uniden PC 76XL
 

On Dec 25, 1:25*pm, "radiosrfun" wrote:
"radiosrfun" wrote in message news:...
Have a Uniden PC 76XL CB set which is emitting an on frequency carrier -
albeit damned near dead - to a near by receiver set to the same channel.
There is no modulation going through it at all ***. There was a partial
leg sticking out of the D8 spot - it was either pulled or fell apart - not
sure which.

*** When I have an External Speaker hooked up via the jack, I seem to get
Modulation through IT and hear it on the near by receiver at the same
time - otherwise I get no modulation at all. The RF meter still isn't
moving in either case. The PA function seems to operate ok, as does all
other functions.

I don't have a schematic for this thing - and was wondering if anyone had
a copy of it they could scan or whatever. The set doesn't "appear" to have
been modified other than the D8 ("possibly" cut).

OH and the finals are good.

Any ideas anyone can lend on the cure of this, would be good too. *Never
seen this issue before. I HATE not having a schematic. That is the biggest
pain in the ass I can think of in this field.

TIA and MERRY CHRISTMAS

OK, I did some research........

First off, "I" am not into "mods" of CBs - so I wasn't sure if this diode
was a part of any Modulation mod. In my research, I found - at least in the
few sites I went to - that the D8 wasn't a part of any mod. So - maybe it
was pulled instead of the D11 - which is stated to be pulled. I'll replace
that first and go from there. I did manage to find the other mod info which
I'm going to check as well - to see if any other tricks await.

I also managed to scrounge up the schematic too - so I should be good to go.
We shall see!- Hide quoted text -

- Show quoted text -

shut up keykween, go crawl back to the basement

Uniden PC 76XL
 

OK, I did some research........

First off, "I" am not into "mods" of CBs - so I wasn't sure if this diode
was a part of any Modulation mod. In my research, I found - at least in the
few sites I went to - that the D8 wasn't a part of any mod. So - maybe it
was pulled instead of the D11 - which is stated to be pulled. I'll replace
that first and go from there. I did manage to find the other mod info which
I'm going to check as well - to see if any other tricks await.

I also managed to scrounge up the schematic too - so I should be good to go.
We shall see!



I also found D11 as the mod limiter. Could be the wrond one was cut. Was it cut
or lifted out entirely? If it was cut, you can repair it with solder.

Vinnie S.

Uniden PC 76XL
 

"Vinnie S." wrote in message
...

OK, I did some research........

First off, "I" am not into "mods" of CBs - so I wasn't sure if this diode
was a part of any Modulation mod. In my research, I found - at least in
the
few sites I went to - that the D8 wasn't a part of any mod. So - maybe it
was pulled instead of the D11 - which is stated to be pulled. I'll replace
that first and go from there. I did manage to find the other mod info
which
I'm going to check as well - to see if any other tricks await.

I also managed to scrounge up the schematic too - so I should be good to
go.
We shall see!



I also found D11 as the mod limiter. Could be the wrond one was cut. Was
it cut
or lifted out entirely? If it was cut, you can repair it with solder.

Vinnie S.

Vinnie,

"Thank you" for trying to help! Yes, in my research - I found D11 was the
one that "should" have been cut/pulled. D8 - was indeed removed purposely -
looking at the solder joints - with the one "partial" leg still there. Also,
I found a mod calling for a "jumper to be placed across D8". So - I'm not
sure if the person thought just pulling it would help! I can't read minds.

As I alluded to in follow up posts, this was a failed attempt to modify.
Once I realized D8 wasn't the one they wanted, replacing D8 restored Tx.
Then there was the talk back resistor put in. I just wasn't sure if the
failed Tx and "talk back" were both linked to a "defect". Without the
schematic, I "didn't" trace it manually and therefore wasn't sure what D8
was for - I hadn't focused any attention yet on the "jacks" where the talk
back resistor was. My main concern was with restoring the transmit. I went
on to check - before replacing the diode - to see if any other pitfalls
awaited me. There were none. If I had googled the Mods for this "first" - I
would have figured it out without posting here. But I was also looking for
the schematic as well, and thought someone here could help out or at least
give some guidance as to some parts.

Well - Kudos to you and Jay for "polite" responses. Thanks for the help and
support.

Uniden PC 76XL
 

"Thank you" for trying to help! Yes, in my research - I found D11 was the
one that "should" have been cut/pulled. D8 - was indeed removed purposely -
looking at the solder joints - with the one "partial" leg still there. Also,
I found a mod calling for a "jumper to be placed across D8". So - I'm not
sure if the person thought just pulling it would help! I can't read minds.

As I alluded to in follow up posts, this was a failed attempt to modify.
Once I realized D8 wasn't the one they wanted, replacing D8 restored Tx.
Then there was the talk back resistor put in. I just wasn't sure if the
failed Tx and "talk back" were both linked to a "defect". Without the
schematic, I "didn't" trace it manually and therefore wasn't sure what D8
was for - I hadn't focused any attention yet on the "jacks" where the talk
back resistor was. My main concern was with restoring the transmit. I went
on to check - before replacing the diode - to see if any other pitfalls
awaited me. There were none. If I had googled the Mods for this "first" - I
would have figured it out without posting here. But I was also looking for
the schematic as well, and thought someone here could help out or at least
give some guidance as to some parts.

Well - Kudos to you and Jay for "polite" responses. Thanks for the help and
support.



I am working ona couple restore projects. One is a tube radio, and I was never
trained on tubes. The other is a TRC-457, which looks hacked. I have determined
that is a bad final, but I think I have to undo the channel mods. They don't
look very good.

Vinnie S.

Uniden PC 76XL
 

"Vinnie S." wrote in message
...

"Thank you" for trying to help! Yes, in my research - I found D11 was the
one that "should" have been cut/pulled. D8 - was indeed removed
purposely -
looking at the solder joints - with the one "partial" leg still there.
Also,
I found a mod calling for a "jumper to be placed across D8". So - I'm not
sure if the person thought just pulling it would help! I can't read minds.

As I alluded to in follow up posts, this was a failed attempt to modify.
Once I realized D8 wasn't the one they wanted, replacing D8 restored Tx.
Then there was the talk back resistor put in. I just wasn't sure if the
failed Tx and "talk back" were both linked to a "defect". Without the
schematic, I "didn't" trace it manually and therefore wasn't sure what D8
was for - I hadn't focused any attention yet on the "jacks" where the talk
back resistor was. My main concern was with restoring the transmit. I went
on to check - before replacing the diode - to see if any other pitfalls
awaited me. There were none. If I had googled the Mods for this "first" -
I
would have figured it out without posting here. But I was also looking for
the schematic as well, and thought someone here could help out or at least
give some guidance as to some parts.

Well - Kudos to you and Jay for "polite" responses. Thanks for the help
and
support.



I am working ona couple restore projects. One is a tube radio, and I was
never
trained on tubes. The other is a TRC-457, which looks hacked. I have
determined
that is a bad final, but I think I have to undo the channel mods. They
don't
look very good.

Vinnie S.

Hacks aside - I LOVE and sometimes miss having worked on CBs. I cut my teeth
on the Tube sets. But being CB died - here - had to move on to something
more profitable.
I have a Lafayette Comstat 25A - that has been a "back burner" project for
some time. It was my mom's radio. Her Brothers's and so on - got her into
CB. Am looking forward to restoring it. I found one for parts locally, so
maybe now is a good of time as any to restore it. I used to love the "tube"
audio. On a cold winter night, between the audio and the glow - it was such
a good feeling.

I love the Internet being - well - at my age - and not being into the
"Mods" - I can research them online OR pick up some info on CBs I might have
forgotten. Be it for profit or not - love working with electronics. But as I
said - when "repairing" - I "hate" not having a schematic. That is like a
major pain in the ass.

My thanks and best wishes to all the "good" guys and girls on here - for a
wonderful - safe - Happy New Year.