Hi all,

Have unsucessfully been searching for a circuit diagram for this Tombstone radio. Hope someone may help me out. Valve line up is 80, 42, 6F7, 6A7.

Tried out a new trick that I was told from someone to identify a valve which had no markings/printing on it. I was told that if you put the valve in the freezer for about a minute it may help bring up the residual printing and hey presto it worked could make out it was a 6A7... clearly. Not sure it is going to work all the time but it worked for that one.

If anyone could help with a circuit diagram for this radio it would be great. My email is peter_ihotmail.com.

Cheers
Peter

  

After another google search I have realise that this set should have 2 x 6F7's. Someone has place a 6A7 in place of the 2nd 6F7. Still no luck with the diagram though.

Cheers
Peter

Http://cgi.ebay.com.au/Schematic-diagrams-Australian-Valve-Radios-Here-/140445329364?pt=LH_DefaultDomain_15&hash=item20b331a7d4

Might be worth a try if there is no member response.

Best of luck.

Thanks for the link STC830. Fingers crossed someone may be able to help out here.

Might be an idea to post a photo of the chassis.

This could be a "badged set" 6F7 is unusual there are Krieslers & Philco's still using them in 1938. No reference to a manufacturer of that name in 1937 trade Annual.

That valve is a Triode Pentode and was used a bit like a 6BL8: Everywhere. It is listed as being suitable for a converter, so the triode may actually be the oscillator. The cathode is common to both elements.

Marc

Marcc, have sent pics to Brad. Laft to right its 42, 80, 6F7 and 6F7 although someone has put in a 6A7 in one of the 6F7 spots instead Hope this helps you help me.

Cheers
Peter

Time will tell as to what I can do to help with this?

6A7 & 6F7 actually have the heaters & cathode on the same pins. What damage was caused to the 6A7 if it was powered up can only be guessed at ; I doubt it helped it, no way it worked unless the circuit was drastically modified.

Marc

Have not fired it up as this is the next project. I'm still on my L plates when it comes to the restoration of the chassis and such, but I get help from a former techy in my area. Have also joined the local HSRA which is helpful. Hopefully the pics will help.

Pictures are up.

Thanks Brad

Cheers
Peter

Can't spot it in the"Rider" on Nostalgia Air but it looks like the era was right for for the chassis being American or based on it.

Automatic Radio Manufacturing Co. Inc. USA

Marc

This is the only info I have on it...

www.hws.org.au/RadioHistory/manufacturers/airmaster.htm

Didnt think it was american. It has ARTS&P, 240v and Australian stations.

No further info: The Goverment introduced local content rules around that time.

Healing was importing Attwater Kent prior to that, then went to making Radio's here with AK circuits.

It is not unlikely that similar went on here. USA does use some 240V. It would only require a transformer change here.

USA tended to use some of the valves in this around 5 years before we did. I have recently worked on a 1934 AWA that had the older 6D6 etc. Yet both Midwests of that era 1934 & 1936, that I worked on recently had octal valves.

Marc

Thanks Marcc for your help. If I find out anymore Info I'll let you know.

Marcc and anyone else who wants to jump in, the latest info I have is that AirMaster was a Brand of the;

Targan Electric Pty Ltd - Brunswick, Melbourne 1930-1937

Does this help any..

Cheers
Peter