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 Modern use of Tube gear.
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 Return to top of page · Post #: 1 · Written at 7:12:36 PM on 2 December 2018.
Unknown's Gravatar
 Location: Shepparton, VIC
 Member since 19 June 2011
 Member #: 931
 Postcount: 24

Hello all, i'm seeking opinions of a service I provide in my local area.
Firstly I restore and repair tube gear, as far as I know i'm the only one in my area for about 150kms.
I'm talking here about respectful restoration, original spec tubes, modern capacitors and resistors of course, either outright replaced or hidden under chassis to preserve looks.
Cabinet repair that does not destroy the character of the item, wood finishes repaired not sanded and replaced, bakelite either replaced with sourced original or tastefully repaired to customer liking.
I try to show respect for the owner's sentimentality or feelings of the item.

All of that said, I have 2 items I use on a daily or near daily basis that I have added or modified in reverseable and non destructive ways.

A Kriesler stereogram that takes external input through reconditioned original design circuitry, (Very easy to do) that has pride of place in my lounge under a 65 inch wall mounted 4k TV, all audio comes from this stereogram.

A hmv mantelpiece am radio with all original circuitry and tubes, it plays abc 774 via bluetooth from pc or phone (somewhat harder).

These units both have all original design or components and will function as designed from factory as well.
These modifications are hidden under chassis and can be reversed in under 5 minutes.

I have had huge negative feedback from those who collect, stating they are not original and therefore valueless.

As my next plan involves similar with and AWA 206cy that I am current seeking help restoring in the TV part of the forum with the thought of adding a switched Composite/tuner input to it I wonder what the thoughts of people here are about this and performing this as a service for other collectors/people.

As I would be asking for help to add a composite to this set and possibly others I value the feedback.


 
 Return to top of page · Post #: 2 · Written at 8:39:08 PM on 2 December 2018.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5239

You are not the only one repairing tube gear in a 150Km radius of Shepparton. I have been doing it for close to 50 years and the Vintage Radio Club of Northeastern Victoria still has members that were, in the time that you seem to have been a member, of this forum, rerpairing.

Some members were actually working at Radio Australia and other installations.


 
 Return to top of page · Post #: 3 · Written at 12:52:55 AM on 3 December 2018.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6678

I have had huge negative feedback from those who collect, stating they are not original and therefore valueless.

It can be argued that anything that has been repaired in any way is no longer "original".

Some people stay awake all night worrying about 100% originality. I'm not one of them. Others, like me, are more concerned with an item being functional. I don't have shelf queen radios. That said, I don't like outright vandalism such as turning a Bakelite radio into a guitar practice amplifier.

Value, like beauty, is in the eye of the beholder. Many people go crazy over the so-called "empire state" radios. I consider them unattractive and of no value to me.

As for the 'negative feedback', opinions are worth what you pay for them, and I'm pretty sure you paid absolutely nothing for the ones you refer to.

Enjoy your own stuff in your own way and to hell with what others may think about that.


 
 Return to top of page · Post #: 4 · Written at 3:30:47 AM on 3 December 2018.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7290

To put everyone's mind at ease, there wouldn't be a single radio left anywhere in the world that is 100% original. As soon as one solder joint, resistor, capacitor, or timber cabinet repair job has been done, it's no longer original. Even the glue used to hold the timber together is vastly different these days.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 5 · Written at 5:27:35 AM on 3 December 2018.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 543

I wonder whether we should be giving negative feedback to the people that throw this gear to the tip. Smile
Restoration, repair and modification as seperate items is what we all do in different circumstances.
Some claim purism and strive for it, but hey it’s a magical hobby and in my case some 55 years ago became a full time job.
JJ


 
 Return to top of page · Post #: 6 · Written at 5:45:33 AM on 3 December 2018.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 1245

Don't listen to the cabinet polishers mate. I don't belong to any Hysterical Radio society and just make things with valves and fix things up so I can learn about the technical side of things. Take a look at the stuff I have posted in the special projects section.
Its nice to restore a car or a radio so it works again and looks like it did when it was made with the same type of components but there is no need to go stupid about it. Like Brad says if you change one solder joint its not original or put it another way if you don't use a rosin stick with you lead/tin solder stick how can you say the solder joint is done the way it was in 1928?

I can certainly see the point of doing a 100 point restoration but you then MUST use the techniques and materials as used for the era of the car/radio/washing machine you are restoring. I used to laugh at car meetings and see a 1920's car finished in 2 pack epoxy paint!
Just fix things up so they work again, clean up and restore so it looks nice to the state you desire and enjoy.
Fred.


 
 Return to top of page · Post #: 7 · Written at 6:43:51 AM on 3 December 2018.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5239

It is amazing how many totally original things turn up. I saw a Crystal Set Saturday that is absolutely original.

The next step is to check it to see if its operable as is.

The next step comes with sets that have been damaged: I have a transistor set with a wooden frame that has been chomped by the battery and have had to neutralise the chemical that took the bottom out of a coffin set. That of course to be repaired, has to be re-timbered.

With a BC-221-N. I wanted that working and presentable for a display. That meant to save its metal work it had to be resprayed (the same way it was) Replace its face as the perspex was too twisted & damaged to be viable and to have it work get rid of a considerable number of dud components The oil filled caps were actually leaking oil as the seals had failed.

This despite the fact that that would likely throw its calibration book into error. However, not everyone want's a "Shelf Queen". So you don't modify the circuit, but accept the fact that to make it work, things like electrolytics & inferior wax paper caps just have to go. I have tested enough wax paper caps, to say testing is a waste of time.


 
 Return to top of page · Post #: 8 · Written at 12:22:25 PM on 3 December 2018.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2363

Getting back to adding a composite input to a vintage TV:

With many TVs this is non-trivial. Easy to get a picture, but a good picture with full use of brightness and contrast and with black level restoration? Another matter! You AWA is simpler than most, having no DC restoration in the first place and a high-level contrast control, but you will still need to get your video signal up to 4v P-P before you inject it at the detector. Then there is the issue of time code and Macrovision blanking which early TVs don't handle well. Your AWA will need horizontal blanking as well.

Consider instead a purpose-designed modulator. I designed a kit for Silicon Chip, who can supply the boards and the hard-to-get-parts.

Here's a link to the thread:

https://vintage-radio.com.au/home.asp?f=6&th=214&offset=1


 
 Return to top of page · Post #: 9 · Written at 2:04:54 PM on 3 December 2018.
Irext's avatar
 Location: Werribee South, VIC
 Member since 30 September 2016
 Member #: 1981
 Postcount: 470

Some restorers go to the trouble of restuffing all paper and electrolytic caps. I don't do this as I figure who is going to look under the chassis. I replace all paper caps with high quality poly caps. All resistors with at least 1 watt types (or higher as required). All electrolytics with usually higher voltage ratings. And generally tidy up all the point to point wiring so that it looks neat and tidy. Above chassis is cleaned up as well as it can be without disturbing things to much. Some restorers completely strip the chassis and repaint it. I find this approach a bit risky as some parts like IF transformers etc are very fragile and not replaceable. The restoration has to satisfy me above all, and if others appreciate it then that's nice also. There are no hard and fast rules for restorations other than safety concerns obviously. Some people get a bit too precious about it all.


 
 Return to top of page · Post #: 10 · Written at 2:10:22 PM on 3 December 2018.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 1253

"Enjoy your own stuff in your own way and to hell with what others may think about that."

Here-here! (or is it hear-hear!), GTC.

A prime reason for collecting is to make sure the items survive into the future. So Unknown, future collectors in fifty years would I hope be grateful that your TVs and radios have survived for their pleasure and interest, because you made respectful modifications to make them useful and hence valuable in another way than originality.


 
 Return to top of page · Post #: 11 · Written at 8:05:24 PM on 3 December 2018.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2149

My very wise sensai Ray Pfister once said to me that repairs are to be expected. There is no guarrantee that original parts will be available. Proper repairs will not destroy the items significance.


 
 Return to top of page · Post #: 12 · Written at 8:16:43 PM on 3 December 2018.
Unknown's Gravatar
 Location: Shepparton, VIC
 Member since 19 June 2011
 Member #: 931
 Postcount: 24

In reference to what marcc said, I practised as a hobby yes years ago, now I also repair for the public as well.
What I meant to say was I am the only one I know of in that radius repairing for others, I do not know of any shop you can walk into or any person to contact to have such items repaired. - I meant no offense.

Thanks for your replies, Its nice to know that my experince is not usual.

I plan to specialise somewhat in this area because as far as I know no one near does for this kind of repair/modification.
Then again I tend to get the odd jobs anyway due to lack of interest from others things like arcade machines, reel to reel, consoles, car audio and the like.

Ian Robertson, the reason I want composite for this is because of the application, I would like to be able to flick a switch and tune a vcr and play a tape. the primary source I would like to hide inside the unit and it outputs composite video but can natively scale a 1080p video to its output.
i would like to have it completely hidden so the cabinet looks original front to back without using the 300 ohm connector.


 
 Return to top of page · Post #: 13 · Written at 5:40:51 AM on 4 December 2018.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5239

The Americans (I am a moderator on their big forum) constantly mention devices that can transmit radio signals around the house in a similar fashion to WiFi & probably pre-dates it.

There is on that forum plenty of discussion on coupling modern ipads & such to old radio's, a large proportion of which are live chassis. Membership is in the order of 10,000.

As said I am in that repair radius, there are about 9 devices in the line currently, & I have had sets from as far away as Geelong. I say devices as two are test instruments. Some are not valve & some things I get are Automotive. I am on a Farm so Radios are not exclusive. Yesterday it was a welder & its never unusual for a tractor or a farm water pump to be here for a repair.


 
 Return to top of page · Post #: 14 · Written at 8:34:28 AM on 4 December 2018.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2363

Unknown from Shepparton:

I did temporarily add a composite video and audio input to my AWA, same vintage, when I was evaluating it prior to stripping the tuner down. It's true you can get better quality this way if you engineer the interface correctly.

I have a lot of experience designing AV interfaces for TVs, having built a business on doing just that, many years ago. We sold interface kits to NEC, AWA and Philips.

Your AWA is a practical case, many other TVs of the period are not. I can help you with this if you want to do it.

But there are other issues with the AWA if you wish to display videotape. The Synchroguide circuit it uses does not play well with VCRs. You can modify it to improve its performance without making it perfect.

Many old TVs false-trigger on the VCR's head switching noise giving you a jumpy picture.

And if your tape contains macrovision it's likely the AWA will not blank it properly and you will get intermittent diagonal white lines.


 
 Return to top of page · Post #: 15 · Written at 5:29:59 PM on 4 December 2018.
Redxm's avatar
 Location: Tamworth, NSW
 Member since 6 April 2012
 Member #: 1126
 Postcount: 466

Didnt EA or SC do a macrovision remover project years back? Would that be helpfull here?


 
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