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Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only. |
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14th Dec 2018, 2:59 pm | #1 |
Nonode
Join Date: Oct 2017
Location: Bristol, UK.
Posts: 2,364
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Dial Wire Mullard 281/15
Hello folks,
I am mid-restoration of a wood-cased Mullard MAS281/15 aka Philips 170A (Bakelite version). I have completed the electronic work satisfactorily and now working on the cabinet and mechanical bits. The tuning cursor drive was a lash-up with bits of string and a length of nylon cord so needs replacing. Following previous advice here I purchased a reel of 0.3mm Beadalon which is perfect for the application. As I removed the old tuning cursor cord (the outer one) from the large brown Bakelite? pulley attached to the tuning capacitor, I found both ends wound around a tiny brass pulley (about 5mm diameter) located immediately behind the slot at the rear of the large brown pulley. I think its purpose is to reduce the bend radius on the cursor drive wire as it passes through the large pulley and doubles-back on itself before heading to the anchor lug (see sketch). The tiny brass pulley had a blob of glue on it so it looks like at one time it might have been glued to the rear face of the brown pulley to hold it in place. It is difficult to get the tiny brass pulley to remain in place unless I glue it again. Any tips and advice gratefully received. To glue or not to glue - that is the question. Cheers, Jerry |
14th Dec 2018, 3:35 pm | #2 |
Octode
Join Date: Nov 2010
Location: Cullompton, Devon, UK.
Posts: 1,434
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Re: Dial Wire Mullard 281/15
On your diagram there seems to be a missing tension spring, when I have replaced these cables in the past due to there springiness I have cut off pieces tape to hold in place,for
the ends I used bootlace ferrules crimped with a little nail varnish to stop slippage. If you have the VSRD disk look up Philips 170A, Manufacturers Manual. John Last edited by jonnybear; 14th Dec 2018 at 3:47 pm. |
14th Dec 2018, 3:48 pm | #3 |
Nonode
Join Date: Oct 2017
Location: Bristol, UK.
Posts: 2,364
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Re: Dial Wire Mullard 281/15
Hi John, thanks for your reply, that makes sense. I can probably find a suitable replacement spring. I'm still thinking that the tiny pulley would have to be glued in place (or maybe it was an addition put in by an earlier restorer?) otherwise the tension in the drive wires won't hold it in place. Cheers, Jerry
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14th Dec 2018, 3:53 pm | #4 |
Octode
Join Date: Nov 2010
Location: Cullompton, Devon, UK.
Posts: 1,434
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Re: Dial Wire Mullard 281/15
I think the brass lug should be fixed as it does not need to rotate use a little araldite.
John |
14th Dec 2018, 3:57 pm | #5 |
Nonode
Join Date: Oct 2017
Location: Bristol, UK.
Posts: 2,364
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Re: Dial Wire Mullard 281/15
OK, thanks
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14th Dec 2018, 4:03 pm | #6 |
Octode
Join Date: Nov 2010
Location: Cullompton, Devon, UK.
Posts: 1,434
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Re: Dial Wire Mullard 281/15
PM sent
John |
16th Dec 2018, 11:01 pm | #7 |
Nonode
Join Date: Oct 2017
Location: Bristol, UK.
Posts: 2,364
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Re: Dial Wire Mullard 281/15
Sorted now, thanks to John. This radio performs very well for a short superhet if you can call it that (I'm thinking of the EBL31) - probably the RF amp stage makes all the difference. Mods please close.
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