UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Audio (record players, hi-fi etc)

Notices

Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment.

Reply
 
Thread Tools
Old 8th Dec 2017, 11:08 pm   #41
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

To be entirely honest Mike I haven't understood your contributions other than at a superficial level, which is of course entirely due to my ignorance. Please don't be offended by my lack of acknowledgment to your posts. My hope is that as my knowledge grows as I resurrect this record player I come to properly appreciate the points you are making.
Nick.
SurreyNick is offline   Reply With Quote
Old 9th Dec 2017, 10:40 am   #42
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

Service Manual for Plessey Type D autochanger / HMV48700 deck

You can get a copy of the Service Manual for this deck from http://www.shopingathome.com/Circuit...0Lists/HMV.htm

It is a comprehensive 41 page manual, with plenty of exploded views and covers; Operation, Maintenance, Adjustments, Faults and Spare Parts, and is available as a PDF download or in printed form/CD.

Nick.
Attached Thumbnails
Click image for larger version

Name:	HMV48700 Autochanger.jpg
Views:	21
Size:	88.1 KB
ID:	153649   Click image for larger version

Name:	HMV48700 Autochanger photo.jpg
Views:	35
Size:	194.9 KB
ID:	153650  
SurreyNick is offline   Reply With Quote
Old 9th Dec 2017, 11:22 am   #43
Edward Huggins
Dekatron
 
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 3,883
Default Re: Restore an HMV 2127

That's very useful. Even so, we rarely come across them as they were mainly used on early 1950s period HMV Radiograms, Table Radiograms and I think one portable Record Player.
__________________
Edward.
Edward Huggins is offline   Reply With Quote
Old 15th Dec 2017, 4:39 pm   #44
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

Other than the usual preliminary checks prior to powering up, do you think I should replace any of the caps in this machine? The smoothing can looks to be in good nick and I'll take it out of circuit to do a quick electrical test, but in the absence of service data, which I simply can't find for this player, I don't know if I should automatically replace any of the other caps.

It's very difficult to get a clear view of all the components and if I don't have to dismantle the machine to get at them it will be a bonus.

Views?

Thanks

Nick
SurreyNick is offline   Reply With Quote
Old 15th Dec 2017, 4:53 pm   #45
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 5,596
Default Re: Restore an HMV 2127

The audio output g1 coupling capacitor at least, can you post an underneath view of the amplifier chassis?

Lawrence.
ms660 is online now   Reply With Quote
Old 15th Dec 2017, 5:27 pm   #46
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

Pics attached. Best I can do without dismantling the machine. I have taken plenty more if needed
N.
Attached Thumbnails
Click image for larger version

Name:	HMV2127 below chassis 01.jpg
Views:	47
Size:	113.6 KB
ID:	154031   Click image for larger version

Name:	HMV2127 below chassis 04.jpg
Views:	43
Size:	152.0 KB
ID:	154032   Click image for larger version

Name:	HMV2127 below chassis 02.jpg
Views:	43
Size:	161.7 KB
ID:	154033   Click image for larger version

Name:	HMV2127 below chassis 06.jpg
Views:	45
Size:	92.7 KB
ID:	154034   Click image for larger version

Name:	HMV2127 below chassis 12.jpg
Views:	39
Size:	103.9 KB
ID:	154035  

SurreyNick is offline   Reply With Quote
Old 15th Dec 2017, 6:31 pm   #47
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 5,596
Default Re: Restore an HMV 2127

That brown hunts capacitor that's connected between pins 1 & 9 of the ECL83 is the grid coupling capacitor to the audio output (pentode) section of that valve, that must be changed at least.

Check the HT electrolytic can for any signs of bulging of the can or the base also check the base and the tag rivets for any signs of chemical leakage, if all's ok it might survive.

You should be able to reverse engineer a schematic for that, it would be good practice for you and also good for the forums collection of odd ball schematics (stuff not on Pauls downloads or DVD)

The red and silver resistor and the electrolytic capacitor connected across it are the triode sections cathode bias resistor and bypass capacitor, the resistor is a 2.2k job, the 100 k resistor connected between the triode section anode (pin 1) and the pentodes screen grid (g2..pin 8) should be the triodes anode load, what looks like a 330k? resistor appears to be the pentodes g1 (pin 9) return resistor, the 470k (nearly shorting out to chassis) appears to be a feedback resistor from the pentodes anode (pin 6) via the anode tag of the sound output transformer to the triodes anode (pin1), both the screen grid and the HT feed to the sound output transformer seem to be connected to the HT filter capacitor, the big dog bone resistor is the HT filter resistor.

Any errors then guilty as charged.

Hope this will help you as to what's what circuit wise.

Lawrence.

Last edited by ms660; 15th Dec 2017 at 6:42 pm.
ms660 is online now   Reply With Quote
Old 15th Dec 2017, 8:11 pm   #48
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

Thanks Lawrence, I'll replace as recommended.
Happy to have a go at generating a schematic. If it were a 30s TRF I'd be very confident but I'm not quite as confident with this, although thankfully it looks quite straight forward. Let me have a go and perhaps someone would be good enough to look over it before I post it up
Nick
SurreyNick is offline   Reply With Quote
Old 16th Dec 2017, 10:18 am   #49
Edward Huggins
Dekatron
 
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 3,883
Default Re: Restore an HMV 2127

Quote:
Originally Posted by SurreyNick View Post
Just been reading the 'reviving your old record player' guide on this forum and it mentions that portable domestic record players with the facility for an add-on speaker/amp unit for stereo reproduction are quite common.

This got me to wondering if this is this a mod that could be made to a record player such as mine?

For the moment I don't have any plans to do anything other than get this player working properly but I would still be interested to know.

Nick
Don't think me harsh, but I would abandon any plans to install a stereo cartridge, re-wire the arm and source/build a stereo converter. As previously advised, the Tone Arm in the Plessey unit is totally unsuitable for satisfactory stereo performance. Just concentrate on getting what you have working as an original, self-contained Mono unit.
__________________
Edward.
Edward Huggins is offline   Reply With Quote
Old 16th Dec 2017, 2:28 pm   #50
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

No offence taken Edward. I have no plans to attempt anything other than getting the player working. The question was of academic interest only.
Nick.
SurreyNick is offline   Reply With Quote
Old 17th Dec 2017, 1:33 am   #51
Boater Sam
Nonode
 
Boater Sam's Avatar
 
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 2,753
Default Re: Restore an HMV 2127

Is that mains voltage selector on the correct setting for your supply?
__________________
Boater Sam.
BVWS Member
Boater Sam is online now   Reply With Quote
Old 17th Dec 2017, 11:31 am   #52
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

No it's not Boater Sam. You are as eagle-eyed as Nuvistor, who spotted it too
Nick
SurreyNick is offline   Reply With Quote
Old 22nd Dec 2017, 4:43 pm   #53
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

I managed to get a New Old Stock BSR-X5M cartridge with stylus and mounting clip (pics attached). I don't know how well is has been stored over the years but at first glance it looks clean and bright with no tarnishing to the metal. Is it safe to assume it will be OK or should I subject it to some sort of testing first?

Nick.
Attached Thumbnails
Click image for larger version

Name:	BSR X5M 01.JPG
Views:	24
Size:	136.4 KB
ID:	154371   Click image for larger version

Name:	BSR X5M 02.JPG
Views:	23
Size:	143.3 KB
ID:	154372   Click image for larger version

Name:	BSR X5M 03.JPG
Views:	23
Size:	125.4 KB
ID:	154373   Click image for larger version

Name:	BSR X5M 04.JPG
Views:	20
Size:	106.2 KB
ID:	154374   Click image for larger version

Name:	BSR X5M 05.JPG
Views:	17
Size:	110.8 KB
ID:	154375  

SurreyNick is offline   Reply With Quote
Old 22nd Dec 2017, 5:07 pm   #54
D_S_J_R
Heptode
 
D_S_J_R's Avatar
 
Join Date: Oct 2010
Location: Suffolk Coastal, UK.
Posts: 581
Default Re: Restore an HMV 2127

Ok, you're done...

I was going to suggest looking out for an ORIGINAL Ronette Stereo 105. I've got one and it does sound great at 6 - 8g tracking... Modern reproductions aren't too good in my experience.

The BSR you've bought is great too, so don't worry. If you can't carefully work around the cartridge weight vs tracking weight differences, you may need some blue-Tac ballast perhaps. I don't know the deck at all so can't offer anything other than to check for dried out grease and lubrication of the motor, idler and main bearing bearings...
__________________
Best wishes,

Dave
D_S_J_R is offline   Reply With Quote
Old 22nd Dec 2017, 5:29 pm   #55
Edward Huggins
Dekatron
 
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 3,883
Default Re: Restore an HMV 2127

Quote:
Originally Posted by SurreyNick View Post
I managed to get a New Old Stock BSR-X5M cartridge with stylus and mounting clip (pics attached). I don't know how well is has been stored over the years but at first glance it looks clean and bright with no tarnishing to the metal. Is it safe to assume it will be OK or should I subject it to some sort of testing first?
You were lucky to source this. The best way to test this is to fix it in and play it.

I notice it has a high compliance stylus which would be great in the right arm, but I'm still not too sure how that old Plessey arm will cope with it. As I have said before, you are trying to defeat the Laws of Physics by trying to make this something it can never be.
__________________
Edward.
Edward Huggins is offline   Reply With Quote
Old 22nd Dec 2017, 5:34 pm   #56
SurreyNick
Heptode
 
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 695
Default Re: Restore an HMV 2127

Thanks. Fingers crossed and all that.

According to the manual I obtained for this deck it is possible to adjust the tracking weight....

Adjustment Of Stylus Pressure
"This may be carried out with a thin 4BA spanner on the hexagon C. Turning the hexagon clockwise (upwards) decreases the stylus pressure on the record and vice-versa.
The recommended pressure measured at the stylus is 15-18 grammes with the 78 r.p.m. head and 11-13 grammes with the 33/45 r.p.m. head."


I don't know if I can get the weight low enough for the BSR-X5M (it's much less than the existing cartridge), but at least I can give it a go.
Attached Thumbnails
Click image for larger version

Name:	Adjustment.jpg
Views:	20
Size:	48.0 KB
ID:	154376  
SurreyNick is offline   Reply With Quote
Old 22nd Dec 2017, 9:16 pm   #57
Audio1950
Nonode
 
Join Date: Nov 2008
Location: Whittlesey, near Peterborough, Cambridgeshire, UK.
Posts: 2,935
Default Re: Restore an HMV 2127

Quote:
Originally Posted by SurreyNick View Post
According to the manual I obtained for this deck it is possible to adjust the tracking weight....
I don't know if I can get the weight low enough for the BSR-X5M (it's much less than the existing cartridge), but at least I can give it a go.
That's good news! You should be able to fix the new cartridge into the headshell
using the single screw hole that was used for the old one. You will probably be able to get the weight down to around the 5 gram mark, but my concern is that there will not be enough weight in the arm to trip the knock-off mechanism at the end of the record, and the arm will stick at that point. We'll see......
Audio1950 is offline   Reply With Quote
Reply

Thread Tools



All times are GMT. The time now is 10:09 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Copyright ©2002 - 2018, Paul Stenning.