Welcome to Australia's only Vintage Radio and Television discussion forums. You are not logged in. Please log in below, apply for an account or retrieve your password.
Australian Vintage Radio Forums
  Home  ·  About Us  ·  Discussion Forums  ·  Glossary  ·  Outside Links  ·  Policies  ·  Services Directory  ·  Safety Warnings  ·  Tutorials

Tech Talk

Forum home - Go back to Tech talk

 64-52 Little Nipper
« Back · 1 · 2 · Next »
 Return to top of page · Post #: 16 · Written at 12:36:55 PM on 23 December 2011.
Little Nipper's Gravatar
 Location: Australia, SA
 Member since 21 December 2011
 Member #: 1047
 Postcount: 85

Marcc,
It looks like I said the "P.T. has a silver case". I meant a plated steel band around the laminations. I think I understand the 'can' now.
All my references have been about the matching transformer for the speaker.


 
 Return to top of page · Post #: 17 · Written at 12:40:58 PM on 23 December 2011.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6688

Okay, schematic etc sent. You can hide your email address again if you wish.

Naked asbestos can be found in some early sets in the form of a heat shield. It was also sometimes used as a filler in bakelite compound, so not a good idea to inhale bakelite dust if filing or drilling it.


 
 Return to top of page · Post #: 18 · Written at 1:57:25 PM on 23 December 2011.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7307

I know these are only plastic but as somebody else here said "I had one of these when I was a kid".
What I would really like is a FM radio. Were any of these made in Australia?


In a word, no. FM receivers didn't arrive until the solid state era in Australia. FM was experimented with during the late 1940s but this was shelved by the Commonwealth Government in favour of television broadcasting. Analogue television in Australia transmitted the picture signal in AM and the sound signal in FM, so building an FM radio based on valves would be fairly easy if you are savvy enough to study how the television receives the FM signals. You could even modify a valve chassis if you had enough experience with valve televisions. The FM band fell within Australia's VHF television band so deletion of the picture circuit (including its deadly EHT components) and modification of the tuner should be all that is required.

If you want to listen to a ready-made FM radio then you would need to turn to Germany. The Germans made some good AM/FM valve radios and the typical brands were Philips, Grundig, Nordemende and Telefunken. These radios were quite complex in their design compared to Australian ones.

Asbestos is still used in top quality brake shoes among other things. Where is the asbestos in radios?

A fair number of timber radios had an asbestos lining inside above the two valves that are notorious for heat, the 5Y3G rectifier and 6V6G power amplifier. HMV is one brand that comes to mind. The famous AWA Radiolettes of the mid-1930s had an asbestos pad between the 80 rectifier and the filter condenser at the back of the chassis.

What is an ISO?

If you are referring to photography, the ISO is the film speed - too slow and photos will blur, too fast and photos will be under-exposed. Even though digital cameras don't contain film they are programmed to simulate conditions met with standard photography.


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

 
 Return to top of page · Post #: 19 · Written at 9:57:12 PM on 23 December 2011.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5257

The inside of the pan is where all of the resistors & caps are, That transformer is the common type. It may well be original often they had dates on them.

The ISO is a common type transformer only It is sheilded within a pressed metal can and the frame of the transformer within is normally alive.

That is supposed to prevent primary failure by keeping it all close to the same voltage and reduces corrosion (apparently?).

The ferrite is getting towards the end of that model series.

Marc


 
 Return to top of page · Post #: 20 · Written at 9:32:47 AM on 25 December 2011.
Wa2ise's avatar
 Location: Oradell, US
 Member since 2 April 2010
 Member #: 643
 Postcount: 830

"This carbon tax will be a good thing. It is about time someone stopped the volcano's from erupting and disrupting the worlds transport."

That's why I avoid buying real estate with volcanos on it. I couldn't afford the carbon tax on a volcamo anyway. Smile

"If you want to listen to a ready-made FM radio then you would need to turn to Germany."

There were many FM tube sets made in the USA in the 50's and 60's. You'd need to do something about the power transformer at 120V 60Hz though.

It's still Christmas Eve here in the USA.


 
 Return to top of page · Post #: 21 · Written at 11:35:45 AM on 25 December 2011.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7307

WA2ISE, I got your e-mail with the audio clip the other day though your ISP is blocking my mail server so my reply hasn't got through yet. I've asked them to unblock it and they seem keen to do so, so standby for a reply with a link to the file so you can link to it in a post of your own.

There were many FM tube sets made in the USA in the 50's and 60's. You'd need to do something about the power transformer at 120V 60Hz though.

Quite true. Those receivers that do not contain transformers should operate fine at 50Hz though those with transformers are another issue - they'd need to have enough iron in the cores to protect the windings from overheating.

Both types of receiver would require a 240/120 stepdown transformer though these are readily available from several manufacturers and one is Flanagan Transformers in Wetherill Park, NSW and these are reasonably priced. Jaycar also have several and again, reasonably priced.


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

 
« Back · 1 · 2 · Next »
 You need to be a member to post comments on this forum.

Sign In

Username:
Password:
 Keep me logged in.
Do not tick box on a computer with public access.