On the tube equipment which I restored, I always remove the selenium rectifier and replace with a normal silicon rectifier, and then a series resistor on the B+ line - generally a 100 ohm 10 watt. That has 2 benefits, one - to drop the increased silicon voltage to the required level, and two - to act as an inrush limiter.

The Selenium stinks when it fails, and the small extra effort to change it when the radio is in for its initial work, is well worth it to prevent a subsequent service call. 

Hi gents,

thanks for for the feedback. It turned out to be T4 and/or T5 - both BC337 type transistors on PCB1. Power was leaking back to motor during standby. All working 100% again. 

Thanks 

That's not the first time we see problems with the BC337 transistors in these decks.

Thanks for telling us your findings!

Martin

Interesting findings here; picked up a BG6500 yesterday which was working before I loaded into the car and when I came home totally dead. Fuse was blown which I replaced and what I can figure out is that the fuse seems to either blow directly when connecting the 230V or when I press the play button. The Power Supply board PCB2, how do one take this out without damaging it since one of the TR's is fitted to the bottom of the Beogram with a heat sink?

Login to view image

The "transistor" (it is in fact a voltage regulator) sits in a socket. The board pulls right up after
you release its holding claw.

This type of filter capacitor (Roederstein) is known to develop shorts.

Martin

Right, taking a closer look now so the regulator is the IC1 7812 and the C3 1000μF is the one you're ref to Martin that most like is the issue here

While looking at the caps they in general looks good; no leakage or any other indications that they're bad but still; if one should pick together a capkit for this BG6500; any recommendation of additional caps to be replaced and as well other components if I'm doing a full overhaul of it?

kimhav wrote:

Right, taking a closer look now so the regulator is the IC1 7812 and the C3 1000μF is the one you're ref to Martin that most like is the issue here

Yes.

kimhav wrote:

While looking at the caps they in general looks good; no leakage or any other indications that they're bad but still; if one should pick together a capkit for this BG6500; any recommendation of additional caps to be replaced and as well other components if I'm doing a full overhaul of it?

No. Just the one
- If it's bad. Check it with an ohmmeter.
You cannot always tell if a component is bad by looking at it.

Martin

Martin you wouldn't know where one could order Vishay 1000uF 40V mounting ring based caps since neither Farnell och TME stocks them.

You can buy the original ROE DIN 41253 1000UF 40V filter capacitor on ebay

Yes I saw that it's possible to get these on eBay but kind of reluctant to get NOS which still could be bad so kind of rather go for Vishay (old Philips) caps (who still makes this mounting ring based cap) or I'll most for Panasonic caps.