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Hi Animal I am one of the moderators on the euro radio co forum. A few have been rejected due to their range of IP address being used by Spammers. What problem did you have trying to register? Did you get activation email? I know you cannot get on if you give invalid information. If you answered all...

New forum http://forum.euroradioco.net

James.

In my first post and only post on this thread. I did ask if the VCO module had failed. If you are going skirt around the truth what is the point in asking the question in the first place. The part has failed or as not. I noted from Rick “Test Your Knowledge” thread’s that he gave start forward answe...

Norm,
Did you have any luck find them as i have been looking for them for the pass 2 years.
I think you can still get them from President but they are pricey.
I know they are special they look like the one from VCR but the connects are in the wrong place.

James.

Good advice keep with stock tran as long as you can.

James.

This is a case of danger.

The diodes will need to be 8 amps or more and you will need a constant load or it will not work.
You will be best off getting the right power supply.

James.

Has the VCO Modula IC2 failed? Has the loop mixer tran TR20 gone low gain? His the cap which go from the input side of the choke which connect to pin 9 of the pll and ground ok? can not read the ref no it looks link 1000u at 10v It is very hard to make out most of the part ref as the circuit diagram...

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 dea...

speedracer6g, I am not trying to run you down. I am now intrigued as to how you get DC Current Gain (Hfe or beta) from a Mosfet, as IRF type Mosfet is just high-speed switch and was never designed for RF applications. Your B&K transistor tester may be you are reading drain current to drain sourc...

Try setting up the PLL section as per http://www.cbtricks.com/radios/rci/rci_ ... ll_adj.htm

James.

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

James.

speedracer6g,
How do you analyzer a Mosfet and come up with the fact they having a higher gian than a RF driver or final bipolar.

I have my doubt that you really know the facts about IRF type Mosfets.

James.

Rick is more often than not on the ball.

James.

You will probably need a buffer amp as you may load the signal from the IC.
Just couple a 10 to 47pF cap an NPN transistor and make up a buffer amp.
This is the best way as you will get a better meter reading.

James.

Did you sort out the main regulator? If you have not fixed the regulator fault then most of the self-biasing circuits in the receiver will be overloaded resulting in poor receiver performance and potential receiver oscillation. You can some times ear this as very low tones just before the second IF ...

I now have 2 of them pick them up at radio Rally.

James.

The voltage on the base tr501 is to low.
I would recheck the zener as the base and emitter of tr34 is incorrect.
You may not be aware that tr34 is an error amp and must be right.

James.

I have been at my good old friend Rick’s workshop when I have seen him fix this problem a few times. Some of the radios have a bad solder joints on the front PCB where the twin pot are solder to and some have a bad connecter plug to the PCB. In most cases its usually just a cold solder joint. Its no...

Jim you got the right guy on the job in Rick.

Just got my radio back from Rick what a great job he as done.
It still hot but not anything like it did and the RX and TX audio no longer cut out.
Thanks Rick I how you a few pints at least.

I am having problems with a new RCI2950DX mosfet radio. I have returned it to the dealer 3 times and still no better. The problem is after 15 minutes of use on FM it gets very hot and cutout the right side is so hot that you can not touch it. it must be a fire hazard. I think it is a very bad radio....

Turner Super Sidekick or +3 desk mike must be in good working order.

I have had 2 CRT SS3900 and both had the trouble with the clarifier. The clarifier is always a bit of and u need to keep adjusting has the radio warms up. My last one which sorted out by Rick is ok and has been for the past 2 years and is used every day mobile. I have known Rick for over 20 years. I...

He has weak rx signal and not overload.
Check d145 and c44.

Hear are some faulty parts i have had in the 3600 PLL section. C101, C102 O/C. R124 gone hi. Bad cap in L22. C225 turn in to a 1.3M resistor. Tr25 low gain. D30 near to short 830 ohm C108 O/C. I use the GRTS method for troubleshoot the PLL/VCO/Mixer circuit. This is the best method can usually find ...