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-   Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players (https://www.vintage-radio.net/forum/forumdisplay.php?f=35)
-   -   How to silence a BSR tape deck. (https://www.vintage-radio.net/forum/showthread.php?t=186724)

Borderer 12th Dec 2021 1:15 am

How to silence a BSR tape deck.
 
3 Attachment(s)
Most of the irritating noise and vibration on the BSR TD2 deck comes from the large rubber idler wheel and its tensioner. Age-hardening of the rubber is partly responsible, but it spoils an otherwise clever piece of engineering.

The idler is redundant on a single-speed drive, and it can be replaced by a direct belt drive from the motor pulley to the flywheel, as fitted to the original TD1 design. Presumably the idler was introduced to enable multi- speed versions.

A readily available 120 x 4mm turntable belt is about the right length - ideally it could be a little shorter - and is easy to fit although some dismantling is required to get the idler assembly out.

The improvement is surprising - almost in another class with much quieter and smoother running - and well worth the effort.

DMcMahon 12th Dec 2021 3:01 pm

Re: How to silence a BSR tape deck.
 
Good information.

David

Vintage Engr 12th Dec 2021 5:24 pm

Re: How to silence a BSR tape deck.
 
That's brilliant. I remember the TD2 when it came out. I shall add the info to my tape recorder servicing data.

Thanks,

David

ben 13th Dec 2021 1:32 am

Re: How to silence a BSR tape deck.
 
Handy mod. Especialy now in view of these machines' age and the idlers are hard to find.
I did this with a Spanish r2r machine that used a similarly noisy idler.

Andrew2 13th Dec 2021 10:02 am

Re: How to silence a BSR tape deck.
 
Very good thinking. These decks were used in a vast number of budget recorders and they did indeed get rumbly as the years passed by.

Restoration73 13th Dec 2021 3:31 pm

Re: How to silence a BSR tape deck.
 
The idea is fine, but note turntable drive belts tend to be thin and stretch might be of
concern, as driving a capstan flywheel with additional pinch roller pressure could
result in a worse wow and/or flutter performance.
A recording made before and played after the change could indicate if this is the case.

My Fidelity Playmaster TR5 with BSR TD2 deck from 1967 continues to function.

Borderer 13th Dec 2021 4:26 pm

Re: How to silence a BSR tape deck.
 
The wow and flutter question is interesting, and I thought it would come up.

I have modified 3 of these decks and they all sounded much the same before and after. I will be testing the current one (on a Fidelity Braemar) as thoroughly as I can when it is finished.

I would have thought that a distorted and unbalanced idler wheel might introduce more w/f than a correctly tensioned belt, and a turntable belt is probably not ideal but it works. The belt I am using is more stretchy (to use a proper technical term!) than the one on my Grundig TK120 but comparable to the belt on my Telefunken M203 so I think it is in the right ball park.

I doubt if the tape transport requires more starting torque than the BSR turntables which used the same motor, and modern belt drive platters are usually heavier so a turntable belt should cope. Long-term it may stretch excessively and slip but it is easily replaced.

I guess there is room for development if anyone thinks it worthwhile.

mole42uk 13th Dec 2021 7:33 pm

Re: How to silence a BSR tape deck.
 
If you want to measure the W&F I have a Ferrograph RTS2 test set you could use if you bring the deck to Bristol.

ricard 13th Dec 2021 8:27 pm

Re: How to silence a BSR tape deck.
 
Does the TD2 have the same idler as the TD10 ? I found out while servicing a TD10 based machine that the idler from various Philips machines from the late 1960s and early 1950s, including the EL3542 (3 of them!) and EL3547 has the correct diameter and shaft diameter. The height of the rim versus the bearing is not identical however, so one has to get creative with some washers to use as shims. But the rubber in that generation of Philips machine seems to be pre-goo era so they can still be serviceable today.

Borderer 13th Dec 2021 8:42 pm

Re: How to silence a BSR tape deck.
 
Quote:

Originally Posted by mole42uk (Post 1432263)
If you want to measure the W&F I have a Ferrograph RTS2 test set you could use if you bring the deck to Bristol.

Richard,

That is a very kind offer and would indeed be interesting, especially if I can find an unmodified deck for comparison. I'll just have to buy another one! Will see how it goes. Thank you.

Tony.

Borderer 13th Dec 2021 8:56 pm

Re: How to silence a BSR tape deck.
 
Quote:

Originally Posted by ricard (Post 1432276)
Does the TD2 have the same idler as the TD10 ? I found out while servicing a TD10 based machine that the idler from various Philips machines from the late 1960s and early 1950s, including the EL3542 (3 of them!) and EL3547 has the correct diameter and shaft diameter. The height of the rim versus the bearing is not identical however, so one has to get creative with some washers to use as shims. But the rubber in that generation of Philips machine seems to be pre-goo era so they can still be serviceable today.

Ricard,

I have not compared with the TD10, but on a quick measurement the TD2 idler is 63mm nominal diameter and runs on a 4.5mm shaft.

Tony


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