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 > Offered and Wanted Messages > Sets, Parts and Service Information Wanted (private buyers only, no swaps)

Notices

Sets, Parts and Service Information Wanted (private buyers only, no swaps) If you need help obtaining components, sets or equipment, post a message here. Private buyers only - no traders. No swaps.

Reply
 
Thread Tools
Old 14th Jan 2020, 2:09 pm   #1
Uncle Bulgaria
Hexode
 
Join Date: May 2016
Location: Cornwall, UK.
Posts: 347
Default Audio Signal Generator & Bench PSU

Ahoy,

I'm on the lookout for an audio signal generator suitable for probing problems in valve and transistor circuits, then aligning them when done. I haven't got into the radio frequency side of things so that's not a requirement. I don't need bells and whistles and complexity, both from being a rank amateur and from being impecunious. Has anyone got one gathering dust?

I've seen some of the marvellous DIY ones on here, but have managed to resist the urge to build a chain of projects to get to fixing the one I started with...

I'd like a PSU to stop me having to make various hook-ups from other pieces of equipment, or have mains floating about while I'm looking at other parts of the circuit. The circuit I'm looking at now has lines up to 44V, so I expect 60V would be more useful than 30. Is a dual supply worthwhile?

I'm considering visiting either Audiojumble or my first foray to a BVWS at Harpenden...perhaps these things are best found at one of those?
Uncle Bulgaria is offline   Reply With Quote
Old 14th Jan 2020, 2:16 pm   #2
HamishBoxer
Dekatron
 
HamishBoxer's Avatar
 
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 7,083
Default Re: Audio Signal Generator & Bench PSU

Yes indeed ,they do turn up at Harpenden and I would say go if you can.
__________________
G8JET BVWS Member and V.M.A.R.S
HamishBoxer is offline   Reply With Quote
Old 14th Jan 2020, 2:26 pm   #3
Radio Wrangler
Dekatron
 
Radio Wrangler's Avatar
 
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 12,929
Default Re: Audio Signal Generator & Bench PSU

Audiojumble and BVWS are possibilities, but you might have better luck at an amateur radio rally, there are often stalls selling second-hand test equipment. I've bought quite a lot of test gear from such events. An element of luck is involved.

Dual power supplies are OK, but you can use multiple supplies at once. Think also of how much current you'll need. Getting one with an adjustable current limit control is a big plus.

Cheapie Chinese power supplies 30v at a few amps are under a hundred quid new and the ones ar work seem to work just fine. Use this as a benchmark for haggling!

Audio generators come in two flavours. Wien-bridge oscillators are low distortion and usually give you sine or square outputs. 'Function generators are more versatile with a menu of different wave shapes, but the distortion on sines is not so good.

David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
Radio Wrangler is online now   Reply With Quote
Old 14th Jan 2020, 3:00 pm   #4
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 8,598
Default Re: Audio Signal Generator & Bench PSU

If you're into tape and general audio a Ferrograph test set is a handy tool when up to spec, eg: Ferrograph RTS2.....Low distortion audio gen, wow and flutter meter, distortion meter, AC voltmeter (wide response) etc etc.

https://www.historyofrecording.com/Ferrograph_RTS2.html

Manual here:

https://www.warwickelectronics.com/i...ers_manual.pdf

Had a Ferrograph test set when I worked for Sony, wouldn't have been without it that's for sure.

Lawrence.
ms660 is offline   Reply With Quote
Old 14th Jan 2020, 3:41 pm   #5
Electronpusher0
Heptode
 
Join Date: Jun 2016
Location: Bognor Regis, West Sussex, UK.
Posts: 520
Default Re: Audio Signal Generator & Bench PSU

I have a Lyons SQ10 spare if thats any good. See photos.
Works OK, the output level pot has been replaced with a 10 turn precision pot with counter.
Being Wein bridge stabilised by thermistor the amplitude does "bounce" a little when first setting frequency but radidly stabilises.
10 plus postage if you want it.

PM me if interested.
Peter
Attached Thumbnails
Click image for larger version

Name:	IMG_2312.jpg
Views:	74
Size:	83.4 KB
ID:	197066   Click image for larger version

Name:	IMG_2313.jpg
Views:	38
Size:	73.5 KB
ID:	197067   Click image for larger version

Name:	IMG_2314.jpg
Views:	36
Size:	75.9 KB
ID:	197068  
Electronpusher0 is offline   Reply With Quote
Old 14th Jan 2020, 5:16 pm   #6
Techman
Nonode
 
Techman's Avatar
 
Join Date: Nov 2009
Location: Lincolnshire, UK.
Posts: 2,672
Default Re: Audio Signal Generator & Bench PSU

A radio frequency generator is a must from what you say in your first post - far more than just an audio frequency generator.

An Advance E2 is the most common and has a fixed audio frequency output as well as all the RF frequencies.

There was someone selling one on here a while ago and I don't think it ever sold, probably because it was a collection only job and the price was a little high at 25 for its condition and for what it was, but maybe worth following up if you can locate the old thread on it.
Techman is offline   Reply With Quote
Old 15th Jan 2020, 1:22 pm   #7
Uncle Bulgaria
Hexode
 
Join Date: May 2016
Location: Cornwall, UK.
Posts: 347
Default Re: Audio Signal Generator & Bench PSU

Strange - I replied to this yesterday!

I've got in touch with ElectronPusher0 as that Lyons seems to be the business.

Techman - I'm intending to test audio circuits and calibrate them with signals specified in the manuals, so what do I need the RF parts for? The Advance E2 looks like the real deal, though!

Radio Wrangler - I have had a check in the paper and online for radio rallies, but I don't think Cornwall supports the density of population. For the PSU, I was thinking a highish current for testing valve heater chains, and a current limiter on the higher voltage for fault conditions in transistors. I don't think it's worth seeking a high voltage supply when the valve equipment's PSU should be able to do that itself. As I don't need all the functions of a function generator, I think the low distortion is for me!

Lawrence - I've had my eye out for an RTS2 for a while. I'd love one! They seem to be just what I need for my interests. However, there was one on eBay for a while for 800, and while one did sell at the BVWS for something much more affordable, it was a couple of years ago so they're not common. But yes, ideal...
Uncle Bulgaria is offline   Reply With Quote
Old 15th Jan 2020, 1:36 pm   #8
PsychMan
Octode
 
PsychMan's Avatar
 
Join Date: Jun 2013
Location: Fleet, Hampshire, UK
Posts: 1,308
Default Re: Audio Signal Generator & Bench PSU

Quote:
Originally Posted by Techman View Post
A radio frequency generator is a must from what you say in your first post - far more than just an audio frequency generator.

An Advance E2 is the most common and has a fixed audio frequency output as well as all the RF frequencies.

There was someone selling one on here a while ago and I don't think it ever sold, probably because it was a collection only job and the price was a little high at 25 for its condition and for what it was, but maybe worth following up if you can locate the old thread on it.
That was mine. Its sold now, in the end I listed on ebay and within 5 hours had a commitment to buy it for 35 and collect it the next day.
PsychMan is online now   Reply With Quote
Old 15th Jan 2020, 2:49 pm   #9
Restoration73
Octode
 
Restoration73's Avatar
 
Join Date: Jun 2013
Location: Surbiton, SW London, UK.
Posts: 1,737
Default Re: Audio Signal Generator & Bench PSU

RTST2 ;
http://www.stewart-of-reading.co.uk/
Restoration73 is offline   Reply With Quote
Old 15th Jan 2020, 3:09 pm   #10
See_Mos
Hexode
 
Join Date: Nov 2003
Location: Ossett, West Yorkshire, UK.
Posts: 286
Default Re: Audio Signal Generator & Bench PSU

If it is still there, grab it, it's a bargain. Otherwise, I still have a Ferrograph RTS2 and ATU for sale at 250 the pair if you don't find anything else

Intended as a tape recorder test set the RTS2 incorporates an audio oscillator and distortion meter as well as wow and flutter, audio millivolt meter etc and I have two 3KHz test cassettes for wow and flutter.

I have owned them from new and they have had very little use. They are in excellent condition. Until 12 months ago they were stored in a heated workshop, now they are in the loft.

Last edited by See_Mos; 15th Jan 2020 at 3:16 pm.
See_Mos is offline   Reply With Quote
Old 15th Jan 2020, 11:57 pm   #11
Uncle Bulgaria
Hexode
 
Join Date: May 2016
Location: Cornwall, UK.
Posts: 347
Default Re: Audio Signal Generator & Bench PSU

Great find, Restoration73 - I have sent them an e-mail. Fingers crossed!

Thank you too, See_Mos for the generous offer. Alas, 250 is too much for me to justify, though they look marvellous pieces of kit - I imagine myself as being at the stage of most people on this forum in the '60s & '70s - bodging things up for cheapness! If I can get the Stewart's RTS2 at 50 I'll be very happy.
Uncle Bulgaria is offline   Reply With Quote
Old 16th Jan 2020, 3:30 pm   #12
Uncle Bulgaria
Hexode
 
Join Date: May 2016
Location: Cornwall, UK.
Posts: 347
Default Re: Audio Signal Generator & Bench PSU

Alas, the Stewart's one has gone...
Uncle Bulgaria is offline   Reply With Quote
Old 16th Jan 2020, 4:48 pm   #13
Techman
Nonode
 
Techman's Avatar
 
Join Date: Nov 2009
Location: Lincolnshire, UK.
Posts: 2,672
Default Re: Audio Signal Generator & Bench PSU

Quote:
Originally Posted by Uncle Bulgaria View Post
signal generator suitable for probing problems in valve and transistor circuits, then aligning them when done.
I know you said 'audio' in your first post, but the statement you made above regarding 'aligning' really refers to RF and IF circuits in radios. Forgive me if I'm wrong, but your statement above tells me that you don't really know exactly what you do want.

I've got a nice Advance audio signal generator with all the audio frequencies on it and to be truthful, I used it just once last year and that was only because it happened to be easier to grab and take into another room as it didn't have things connected up to it, which was the case with the E2 which would have been just as good for the purpose with its single fixed audio frequency.

If you're going to be working on radios, then you'll need RF frequencies. If you're just going to be working on audio gear, the go for an audio generator only, but if you're thinking that you'll need all those audio frequencies for what you intend to do, then you're going to need a lot more kit than just that generator.

I regard a bespoke audio frequency generator the same as a valve tester, as 'nice to have' item to play around with, but completely unnecessary most of the time.

If you've got the chance of an AF generator at the right price, then go for it!
Techman is offline   Reply With Quote
Reply

Thread Tools



All times are GMT +1. The time now is 11:37 pm.


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.