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 Radio (domestic)

Notices

Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only.

Reply
 
Thread Tools
Old 13th Jan 2020, 2:12 pm   #1
60 oldjohn
Nonode
 
Join Date: Dec 2004
Location: East Yorkshire, UK.
Posts: 2,507
Default Radiomobile type A & 4100

The Radiomobile "type A" and 4100 were brought in for repair, can anyone confirm they are a pair? as there is no evidence of them ever working in recent times. Also anyone know where I can get the service sheets?


John
Attached Thumbnails
Click image for larger version

Name:	Radiomobile 010.jpg
Views:	81
Size:	111.9 KB
ID:	197002   Click image for larger version

Name:	Radiomobile 009.jpg
Views:	75
Size:	93.9 KB
ID:	197003   Click image for larger version

Name:	Radiomobile 008.jpg
Views:	58
Size:	64.3 KB
ID:	197004   Click image for larger version

Name:	Radiomobile 007.jpg
Views:	49
Size:	80.0 KB
ID:	197005  
__________________
My favourite text message "Ill be there in five minutes, if not read again"
60 oldjohn is online now   Reply With Quote
Old 13th Jan 2020, 2:51 pm   #2
'LIVEWIRE?'
Dekatron
 
'LIVEWIRE?''s Avatar
 
Join Date: Mar 2006
Location: N.W. Oxfordshire(Chipping Norton)
Posts: 7,191
Default Re: Radiomobile type A & 4100

It's a long time since I've seen either the type 'A' amplifier or the 4100 head unit John, but, AFAIK, they can certainly be used together, provided that the connectors are pin-compatible. Both will be valve-based, and produced around the same time, probably mid to late 1950s or very early 1960s. Somewhere in my 'archives' I may have some service info for either or both. The nearest model in Paul's Service Data Lists is the 4200, which is probably very similar.

Last edited by 'LIVEWIRE?'; 13th Jan 2020 at 2:56 pm.
'LIVEWIRE?' is offline   Reply With Quote
Old 13th Jan 2020, 5:09 pm   #3
ajgriff
Heptode
 
ajgriff's Avatar
 
Join Date: May 2004
Location: Halifax, West Yorkshire, UK.
Posts: 863
Default Re: Radiomobile type A & 4100

The 4100 dates from between 1951 and 1955. The A-Type amplifier was one of the power unit options. Radiomuseum has some information.

Alan
ajgriff is offline   Reply With Quote
Old 13th Jan 2020, 5:32 pm   #4
Hartley118
Octode
 
Hartley118's Avatar
 
Join Date: Aug 2015
Location: Cambridge, Cambs. UK.
Posts: 1,466
Default Re: Radiomobile type A & 4100

AFAIK those two units are a pair..

The type A amplifier is the single-ended power amp. You should find this valve line up: W77, DH77, N78.

Somewhat idiosyncratically, the signal that links the head unit to the amplifier is at IF frequency. It travels in that screened multicore cable along with audio to and from the volume control and the 12V power switching. I've found that multicore cable very vulnerable to breaks. If that's the case, I've found a reliable solution is to replace it with several smaller 4-way cables.

I have circuits and service data, but don't have evidence of where I sourced them from and, after the recent unhappy event, I don't want to risk rustication by publishing them on the forum.

Moderators: what's the correct procedure here please?

Interestingly, I've normally found the paper capacitors in these units to be in decent shape, so it's worth checking before any wholesale replacement.

Best of luck John - when working to spec, these are remarkably sensitive receivers, though bench testing can be problematic due to interference from the vibrator supply.

Martin
__________________
BVWS Member
Hartley118 is offline   Reply With Quote
Old 13th Jan 2020, 5:39 pm   #5
ajgriff
Heptode
 
ajgriff's Avatar
 
Join Date: May 2004
Location: Halifax, West Yorkshire, UK.
Posts: 863
Default Re: Radiomobile type A & 4100

Quote from Forum Rule F4:

"Discussion of motor vehicles is prohibited, but discussion of radio, audio and associated equipment and electric clocks fitted to vehicles is allowed."

You appear to be on safe ground as far as I can see.

Alan
ajgriff is offline   Reply With Quote
Old 13th Jan 2020, 6:48 pm   #6
MotorBikeLes
Octode
 
Join Date: Dec 2012
Location: Kirk Michael, Isle of Man
Posts: 1,394
Default Re: Radiomobile type A & 4100

I think that amp unit contains a non-synchronous vibrator.
I had one, but it may have been a bigger one. Back in 1967 I owned a Healy Abbot DHC, fitted with the radiomobile dashboard unit, and the amp under the bonnet. Two speakers, one in each door. i am fairly sure mine had a dual output (EL41s maybe?). I seem to recall it was longer than your Type A.
I remember trying to get the vibrator to run reliably (gentle filing), but not very sucsessful, so I bought a new replacement. It had a load of black caps, can't recall the make, and the distorted output became acceptable once they were replaced. A long time ago.
Les.
MotorBikeLes is offline   Reply With Quote
Old 13th Jan 2020, 7:02 pm   #7
barrymagrec
Heptode
 
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 587
Default Re: Radiomobile type A & 4100

I have seen two of these amplifier units, one in an R type Bentley, both had a pair of N78s as the output valves and a Plessey 1214 vibrator.

I think the head unit in the Bentley was more involved than this one appears to be.

My understanding was that the connecting lead was tuned for the IF and so the radio would only operate with the length of lead it had been set up for.
barrymagrec is offline   Reply With Quote
Old 13th Jan 2020, 8:03 pm   #8
60 oldjohn
Nonode
 
Join Date: Dec 2004
Location: East Yorkshire, UK.
Posts: 2,507
Default Re: Radiomobile type A & 4100

Thank you all for the replies. Martin, I have sent an Email, it could have gone into the junk mail if you can not find it.


John.
__________________
My favourite text message "Ill be there in five minutes, if not read again"
60 oldjohn is online now   Reply With Quote
Old 13th Jan 2020, 9:20 pm   #9
AC/HL
Moderator
 
AC/HL's Avatar
 
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 7,759
Default Re: Radiomobile type A & 4100

Quote:
Originally Posted by Hartley118 View Post
Moderators: what's the correct procedure here please?
If it's not in VRSD, and in the public domain, there is no problem posting as far as we're concerned. If it was acquired on the understanding that it was not published, that's a matter for the poster. Radiomuseum are one such source, and they take a dim view of watermarked documentation appearing here. If in doubt, just post the minimum required to illustrate a problem.
__________________
Bill, BVWS member
AC/HL is online now   Reply With Quote
Old 13th Jan 2020, 11:05 pm   #10
MotorBikeLes
Octode
 
Join Date: Dec 2012
Location: Kirk Michael, Isle of Man
Posts: 1,394
Default Re: Radiomobile type A & 4100

BarryMgee, YES, they were N78s in my amp. From your comments, it is safe to conclude there WERE two amps. mine in the Healy obviously similar to the one in the Bently. The higher spec model.
Les.
MotorBikeLes is offline   Reply With Quote
Old 13th Jan 2020, 11:22 pm   #11
ajgriff
Heptode
 
ajgriff's Avatar
 
Join Date: May 2004
Location: Halifax, West Yorkshire, UK.
Posts: 863
Default Re: Radiomobile type A & 4100

I think the 4200 was the upmarket model with five pre-set buttons rather than three plus improved sensitivity.

Alan
ajgriff is offline   Reply With Quote
Reply

Thread Tools



All times are GMT +1. The time now is 12:40 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 - 2020, vBulletin Solutions, Inc.
Copyright ©2002 - 2020, Paul Stenning.