The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

Hi Allen: Sorry it's taken so long to reply but been a bit busy, unfortunately the old timer who said you need Xtals for the Reace was right. The circuit inside the unit is a colpitts oscillator with tripler so for whatever channel you want to transmit a test signal on you need a xtal approximately ...

Hiya & thanks for the info: As far as I know you dont need Xtals to go in the front the 2 sockets are used for quick Good / Bad testing of Xtals, it won't tell you the actual Xtal fequency but will tell you if it's capable of sustaining oscillation. The bottom scale is marked Xtal: Good or ?, do...

Hi 222: Can't argue with that mate, seen it many times where Tech's have repaired a faulty radio by changing a non faulty component. As you said the problem was cold solder joints in the first place, a high power illuminated magnifier is a godsend on any bench for finding cold joints & even then...

Hi Johnno: A 60MhZ scope is ideal for radio servicing work, try to get a good make such as Hitachi, Gould, Hameg, Tektronix etc as these are made to good spec. Also make sure you get the test probes, power lead & if possible the user manual for it. When looking at scopes on ebay look for scopes ...

Hi: You say your pretty much the local Tech now, what test equipment do you have available to you ?? Do you have a good Digital meter & audio signal tracer or Scope ?? If not your going to seriously struggle. What is the component number next to the diode ? I don't have the CCT for this 1 only t...

Hi: Have you looked in the manuals section of www.cbtricks.com ?

Andy @ Classic CB

Possibly the Audio output chip has had it, if you don't have the test gear to check it out your best bet is to take it to your local Tech.
If you open it up you may well do more damage to your radio.


Andy @ Classic CB

Hi Lance: Only seen this once before, but i normally don't bother with aerials. If the magmount has a rubber boot fitted, take it off. also check that where the whip screws in you have nice shiny threads for contact. You may also have to increase your earthing to the antennae. Regards: Andy @ Classi...

Hi All: Picked 1 of these up from ebay at a good price, wondering if any of you nice people might have a user manual or Data sheet for it & if so could you email me a copy.

Thanks: Andy @ Classic CB (UK).

Hi Tony: There are a few good books on CB repair around, but in the end a lot comes down to experience & the test equipment you have available to you. A lot can be done with a good Multimeter & dummy load but for really serious repair work you need a Scope, Frequency Counter & Signal Gen...

Hi: I think the manuals, mod info etc for this radio can be found in the manuals section of www.cbtricks.com & can be freely downloaded from there.

Hope that helps: Andy @ Classic CB

Hi: Sorry missed the bit about it being a new radio when I first read your post, no problem with doing the job inside the Mic but make sure you don't leave the resistor legs bare to short out on anything. Slip a little sleeving over each 1 just to make sure.

Good Luck: Andy @ Classic CB.

Hi: Believe me Ralfs way is the better way, if you try to fit the Resistor inside the Mic plug it's too fidly & very easy to short things out. If you do the Mod inside the Radio you have more room to work & it's easier to do. By the way this Mod does work i've had to do it on a few radio's. ...

Hi: I would be checking the output transistors & driver as a starter. Had 1 of these a while back where the output transistors had been changed for underrated types & had no thermal compound on them, exhibited very similar symptoms. Also make sure you check for dry solder joints around the R...

Hi Joe: 2 Things I would try first: 1) Try a dummy load / Light connected to the Antennae socket, when you key up this will show if you actually have any TX by lighting brightly when you key up, if not then it's Tech time. 2) For the power meter problem then try gently tapping the PCB with the handl...

Unfortunately you probably caused more damage by not having it fixed when you first noticed the problem, sounds like it's time to take it to a GOOD radio engineer.

Andy @ Classic CB

Hi: Does the Frequency change when you move the selector? If not then this would point to a PLL or Power supply fault. Check the voltage on pin 9 of the MB8734 PLL chip, it should be 8v DC if not then this points to a power supply fault & you should check the MB3756 regulator etc. Apparently thi...

Hi: I know this post is a few weeks old but can you tell me if you still have the parts for sale please, if so how much & what would be the carriage to the UK?

My email address: restorer@tesco.net

Thanks: Andy.