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Old 12th Apr 2015, 7:45 pm   #14
dazzlevision
Dekatron
 
Join Date: Sep 2003
Location: Near Swindon, North Wiltshire, UK.
Posts: 3,595
Default Re: HMV model 2401 "Stereomaster" restoration

Hello,

Somewhat later on than planned, I have recently returned to this project.

I fitted an exact replacement second hand EMI tweeter in the left speaker compartment. I also removed the other three speakers ands checked that their voice coils weresn't binding against the magnet (luckily, they were all OK).

After refitting the speakers, I turned to the BSR MA70 record deck. It wouldn't move to the correct point on the record when used in "auto" mode (it only moved slightly towards the record before descending). I checked the adjustments, but they didn't make much difference, so I stripped down the remainder of the deck that I hadn't already attended to and removed old grease and applied fresh. After reassembly, the same fault persisted. After spending some time studying the operation of the mechanism, I couldn’t see any obvious cause, so I fitted a complete sub chassis from a spare MA70 (that I had already stripped, cleaned and relubricated) and that did the trick!

I then set up the usual adjustments and it plays various sized records correctly in manual and auto mode, producing a very pleasing sound. I had problems ascertaining the correct wiring connections to the BSR C1 cartridge, but after posting on this forum (in the last few days: https://www.vintage-radio.net/forum/...d.php?t=115618), I was able to establish the correct terminations (mainly a phasing issue).

The Stereomaster now works very well on VHF/FM stereo radio and disc. It also gives a good account of itself when a good quality tape recorder is connected via the 5-pin DIN "tape" input socket.

Altogether, I have found this to be a very pleasing and informative restoration job, especially as I haven't completely stripped down, cleaned up and relubed a BSR record deck before.

I like the compact appearance of these Stereomasters and the side facing bass/mid speakers still seem to produce a good sound when listening from the front of the unit. The user manual recommends the unit be placed in the corner of the rooms, to allow sound to reflect off the hard walls near them.

The only other thing that I have noticed is a loud click when the deck switch makes or breaks. I am considering fitting a C-R series snubber network or VDR across it.

Regards,

Dazzlevision
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Last edited by dazzlevision; 12th Apr 2015 at 7:51 pm.
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