Chassis RK Circa May 1956

Similar layout to the last Astor circuits in AORSM's However, more valves & different. Numbers off some.

Rec. 6V4; out. 6AQ5. Det/Audio 6AV6 Two RF's appear to be 6BH5 (definately not 6N8) (nine pin). Coverter 6AN7 Permability tuner, not gangs.

It has to be a 9 pin socket that's broken... gotta luv that along with the owners comment "Turned it on lights lit and there was a pop"....... Fancy that!

Looking for circuit & some Knobs if some one can help.

Looks like 80% of the resistors are out of spec. A few paper caps left & the usual dodgy rubber coated wire, a faulty mains plug & a broken dial string.

Someone could also get a real kick out of the live frame audio transformer. No attempt at sheilding.

Marc

Delete reference to circuit (only) scored one.

Glad I did. Previous repairer had made mistakes.

Horror! All original resistors have failed. New caps, new resistors, usual wire, dial string. All 100pF Silver Micas & one 300pF had failed & that's rare.

Marc

This is more like a progress report. Genuine or repro. knobs still an issue.

After a variety of repairs ( module, cabinet, mains & record changer) it is being reasembled. Base board (repaired) is last as I have to align the dial pointer with the dial (on cabinet). Dial string had broken.

Marc

Hi Marc....did you get that project finished? I had a customer drop one of these in for repair last week. Not sure if I'm going to do it as hours of work and they want it fixed for beer money!
Have you got a copy of the circuit diagram available?
Cheers George

Some people do like making a convenience of you. I actually have the info for the Colaro turntable, which will likely need cleaning & re lube, as the old grease soaps will have likely hardened.

I always archive, the odd circuits, especially those not in AORSM's. Checking I have the three Astor sheets scanned & archived.

The set was a pain, from memory as all of the resistor & caps including the Mica's were stuffed. I did wonder if it had been hit by lightning as punishment by the almighty for the type of crap being played?

If I get an email address I can send sheets, I have . Likely in the evening

Marc

Astor RK Service Manual

Thanks for the update.

This one looks like lots of work....may not commit to it yet. Any service info for the unit would be greatly appreciated thanks Marc. I've worked on lots of turntables but not on the Colaro before.

Don't think the Rolling Stones have been anywhere near this machine either. Definitely no satisfaction on the horizon....more of the German marching band territory I suspect hence more lightening from above!

Email is hishothousegmail.com

Thanks Marc. If you're ever in McLaren Vale area let me know.

Cheers George

Link to service manual in Marc's previous post.

Thanks for the service info Marc. Very much appreciated mate.
Cheers George

Thanks very much Marc for uploading the service manual for this. This is fantatic and will make my job much easier when I order parts.
I have been searching for years for one of these table top radiograms and I finally came across one in a perfect cabinet I was lucky enough to pickup on Ebay for $80. Completely original condition with exception to a dodgy cut and tape job to extend the power cord. I opened this up last night and was very surprised and how many components were crammed in the chassis. It's going to be quite a large resto job but one i'm looking forward to.

Probably a stupid question.. and normally I would always earth the chassis when doing a resto but I read above you mentioned the 'live frame audio transformer' I've only had just a quick look at the radio but would this cause any problems if I earthed the chassis? I'm assuming that the audio o/p transformer is physically isolated from the chassis with plastic/rubber grommets etc.. but history dictates to me to never assume anything so I thought I would ask.

Thanks so much.
Aaron

Start again with a new three wire cable & ground the chassis. Tying knots in the cable is now a non no: Use a gland. These can normally be fitted pointy end into the pan.

The biggest problems with a live frame Audio Transformer come when you put your fingers on it. DC is dangerous as it "Grabs" there are much safer ways of getting kick out of life.

Marc

Thanks Marc, I've now grounded the chassis. I had a bit of a 'shock' as I think some one had previously been inside this radio before as there were two extension wires coming out of the back of the unit which I did stupidly assume were ant and earth wires as this is what was marked on the back of the cabinet.. until I touched them! these two wires had been twisted around the primary of the audio transformer!

I've now manged to replace all caps and most resistors (I probably didn't need to replace as many resistors as I did as most of them measured OK but some of them didn't look that great visually so I did them anyway as I don't really want to have to remove the chassis out of this one again for many years.

I'm now working on the Collard turntable which unfortunately has perished idler wheels (one for the turntable and one for the auto arm return/record drop) I've heard that you can get these idler wheels restored with new rubber from an American store but i'm yet to find out where. If anyone knows, if you could let me know that would be great. I have an old BSR turntable that I've restored and thinking about fitting to replace the original Collard but that's going to mean modifying the original metal turntable base which I don't really want to do.