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-   -   B&O radiogram model 1200RG. (https://www.vintage-radio.net/forum/showthread.php?t=145454)

FERNSEH 6th Apr 2018 8:56 pm

B&O radiogram model 1200RG.
 
2 Attachment(s)
I've advised the owner of the this B & O 1200RG radiogram that the best solution to solving his record deck problems might be to replace the original Beogram 1000 deck with a Garrard SP25 or something similar.
First examination of the record deck indicated all that was required to get the record deck going was lubrication of the bearings and a new drive belt.
However, it was noted the speed selector mechanism wasn't working. After dismantling the assembly it was found a "monkey metal" (Zamak) part had disintegrated, see first attachment.
Also the speed selector control knob is broken.
Used replacement parts can be found on eBay but are far more expensive than a good SP25.
Secondhand parts can't be guaranteed to last because these are same the age as the worn out and broken parts in the record player being repaired. The radiogram was bought in 1967.
If genuine new B & O parts are still available it would make still sense to repair the existing record deck.


DFWB.

Edward Huggins 6th Apr 2018 11:23 pm

Re: B&O radiogram model 1200RG.
 
Well, you could spend a lot of time on this I know. An OK Garrard SP25 (or a BSR MP60) would cost on ebay about £50.00 and as long as the cartridge (or one you may need to add) matches the input sensitivity and the correct impedance of the B&O input, might well be worth considering.

Michael Maurice 6th Apr 2018 11:44 pm

Re: B&O radiogram model 1200RG.
 
I would save this deck, its a really good one.

How did you get the pulley off the motor shaft? Spares are NLA from B&O haven't been for decades but I may have a spare part for it.

Radio Wrangler 7th Apr 2018 4:01 am

Re: B&O radiogram model 1200RG.
 
B&O turntable mechanisms are usually worth saving if possible. Decisions about whether it's worthwhile need to take into account the replacement cost of styli if they are available at all.

David

FERNSEH 7th Apr 2018 4:04 pm

Re: B&O radiogram model 1200RG.
 
News Flash! I've ordered the parts we need to repair the Beogram 1000 record deck.

DFWB.

kirstyd 7th Apr 2018 8:38 pm

Re: B&O radiogram model 1200RG.
 
3 Attachment(s)
I have B&O 900 radiogram with the same deck .When first switched on it takes about 5 minutes to get up to speed and as for the styli god only knows what a new one would cost these days .I have these two unopened ones from 1973.The 900 would have been 3 years old by then

Michael Maurice 7th Apr 2018 9:21 pm

Re: B&O radiogram model 1200RG.
 
Quote:

Originally Posted by FERNSEH (Post 1033161)
News Flash! I've ordered the parts we need to repair the Beogram 1000 record deck.

DFWB.

Just out of interest, where did you order them from?

FERNSEH 8th Apr 2018 12:08 pm

Re: B&O radiogram model 1200RG.
 
"Just out of interest, where did you order them from?"

Ebay: A "buy it now" offer.

DFWB.

Studio263 9th Apr 2018 5:57 pm

Re: B&O radiogram model 1200RG.
 
The Beogram 1000 is a proper record player, the SP25 is a silly toy fit only for students and the permanently hard up.

The part you show often comes apart because it is only staked over, it is quite in order to drill it and put an M3 screw through though, there is plenty of room. A few minutes and its done.

These motors are often slow to start and sometimes never quite get up to speed. Tight bearings is the root cause, they are spherical 'oilite' types that seem to gum up with the synthetic oil they used. Oddly, the earlier 42V model doesn't seem to do this nearly as much. The motor shaft is a standard size so an easy way to re-finish the bearings is to take them out and run the correct sized twist drill through them in the fingers (like a very gentle file). Copious amounts of oil on both parts assures a good finish. In and out, twist it round and try it on the motor shaft regularly until the parts rotate easily without "drag".

So far so easy. The trouble is getting the upper one out. The pulley is shrink-fitted on so you need lots of heat to expand it enough to pull it off. A tip is to loosen off the grub screw holding the centrifugal governor to the shaft underneath first, then the fragile disc on which it bears won't get ruined when the shaft moves (otherwise - it will!). The fibre washer under the pulley won't come off in one piece but it isn't that important anyway, I don't worry too much about it. Once the motor is back together you'll have to adjust the height of the governor again, I make it so 33RPM comes in the middle of the range of adjustment after 10 minutes of running. With all the bashing and banging that is sometime necessary to get the pulley off the rotor may well move on the shaft too, so it isn't a bad idea to measure its position from one end first so you know. A few smart hammer taps on the end of the shaft with the rotor supported in a stout vice soon gets it back. Heat up the pulley part and it will just drop on, compared to the aggro of getting it off.

This isn't a task I every particularly relish but its well worth it over a rumbly old Garrard with a big, clumsy arm. They did put AT6s in some of these for those who wanted an autochanger, but there are far simpler ways to ruin all your records if that's what you want to do.

Beobloke 10th Apr 2018 6:16 pm

Re: B&O radiogram model 1200RG.
 
Ouch!

Whilst I completely agree with Studio263's assessment that the Beogram 1000 must stay put in the 1200RG, I cannot let the scurrilous attack on Garrards pass!

After all, lets not forget that in the time it takes one purely to read about how to repair a Beogram motor, one could have stripped, cleaned, repaired and reassembled an SP25 or AT6 motor, made a cup of tea and be halfway through your fist LP side - rumble and all! ;D

GrimJosef 10th Apr 2018 6:50 pm

Re: B&O radiogram model 1200RG.
 
Well I hope you'll have made up over this before the NVCF. I wouldn't want there to be fisticuffs in the exhibition centre car park ;D. (Just for the avoidance of doubt, these two are friends in the real world !)

Cheers,

GJ

tracypaper 11th Apr 2018 1:58 am

Re: B&O radiogram model 1200RG.
 
one could have stripped, cleaned, repaired and reassembled an SP25 or AT6 motor, made a cup of tea and be halfway through your fist LP side - rumble and all!

By the sound of it I could have done all this in the time it takes the Beogram to get up to speed, if indeed it gets there.

Beobloke 11th Apr 2018 8:10 am

Re: B&O radiogram model 1200RG.
 
Quote:

Originally Posted by GrimJosef (Post 1034031)
Well I hope you'll have made up over this before the NVCF. I wouldn't want there to be fisticuffs in the exhibition centre car park ;D. (Just for the avoidance of doubt, these two are friends in the real world !)

We always share a car to the NVCF, and I can promise you the fisticuffs are usually done by somewhere between Didcot and Oxford... ;D

kirstyd 11th Apr 2018 8:04 pm

Re: B&O radiogram model 1200RG.
 
I cleaned and lubricated the motor on mine some years ago by soaking the bearings in hot white spirit [heated with a hot air gun i might add] it was possible to see the dirty lubricant seeping out .After reassembly it worked perfectly for months then i went on holiday for a month when i came back it was back as it was [slow to get up to speed] I have only seen a photo of the B&O 1200 but if it sounds as good as the 900 its well worth the effort

FERNSEH 12th Apr 2018 10:59 pm

Re: B&O radiogram model 1200RG.
 
The replacement parts arrived today. I'm in the process of reassembling the record deck.
I have to say I do like the method B & O have employed to mount the motor assembly on to the deck. Rather than use perishable rubber suspension parts they opted for three tensioned springs positioned 120 degrees about the motor. There's certainly evidence of over engineering here, that's good.

DFWB.

FERNSEH 14th Apr 2018 8:52 pm

Re: B&O radiogram model 1200RG.
 
The reassembly of the Beogram 1000 record deck was completed today. Assuming the strobe on the turntable relates to 33 rpm then the speed is spot on. However, it does take some time for the motor to come up to the correct speed.
But the job is not finished. The tonearm cannot be adjusted correctly, the counter balance weight is too heavy and the stylus does not come into contact with the disc. Any ideas?
The power for the pre-amplifier comes from a winding on the motor. Two OA85 germanium diodes and two 12uF reversible electrolytic capacitors are employed in a voltage doubler circuit to supply -21 volts for the four transistors in the pre-amp.
The capacitors were found to be useless.

DFWB.

kirstyd 14th Apr 2018 9:33 pm

Re: B&O radiogram model 1200RG.
 
the weight may need moving back a little .if its too far forward on the arm it will stop the arm from dropping onto the disc.This may sound silly but is the cueing device down?

FERNSEH 14th Apr 2018 10:59 pm

Re: B&O radiogram model 1200RG.
 
2 Attachment(s)
Hi Kirstyd,
The counter balance weight is pushed forward as far as it can go.
It's a very heavy thing.
DFWB.

Michael Maurice 14th Apr 2018 11:41 pm

Re: B&O radiogram model 1200RG.
 
There should be a spring between the arm housing and the black weight adjuster.

I'll try to take a picture of one tomorrow.

FERNSEH 15th Apr 2018 12:10 am

Re: B&O radiogram model 1200RG.
 
"There should be a spring between the arm housing and the black weight adjuster.I'll try to take a picture of one tomorrow." Hi Michael,
thanks for that. The owner of the radiogram mentioned something to that effect today when I told him the repair to the deck was almost complete except for the tonearm problem.

DFWB.


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