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 Valves for AWA C48 radio
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 Return to top of page · Post #: 1 · Written at 1:05:52 PM on 13 February 2017.
Bushman's Gravatar
 Location: Kempsey, NSW
 Member since 6 December 2016
 Member #: 2019
 Postcount: 33

Hi everyone,

Just removed the chassis from the cabinet and now comparing and contrasting with a AWA C54 circuit diagram as a useful guide in restoring the radio.

While I am doing this I am looking for suggestions on what to do about the missing valves from the radio. About 15 years ago I had the approval and opportunity to look at the house contents that were up for auction prior to the auction day. I noticed this radio and speaker and was interested in it. Before I left I looked in the cabinet and found it was filled with the typical shredded newspaper as bedding for mice. I could just see the glass of the valves amongst the bedding. Unfortunately, I was not able to be at the auction that day as I had other prior commitments. My late mother offered to bid for me and was successful.

Upon receipt of the radio later that day, I noticed the entire loose contents had been emptied (valves and mouse bedding) just prior to the auction........

Researching the internet informed me that the radio uses 5* DEL410 UX valves and 1* DEP410 UX valve. It looks very slim that these types of valves are available so restoring the radio to what it actually was, does not seem to be an option.

Could someone be able to advise what would be the ideal solution and the suitable valves to install. If UX base valves are becoming scarce as replacements for this radio, would it be better to change the sockets to the B4 type which to me seems more readily available.

I do note that while some valves are similar as replacements, it can depend on the particulars of the design of the radio. Given it is a 1928 model radio, I think there is some tolerance for valve variations unlike later years.

Appreciate the help and the direction to take where accessing valves for this radio.

Bushman


 
 Return to top of page · Post #: 2 · Written at 2:39:56 PM on 13 February 2017.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1619

Can I see a photo of this cabinet please.


 
 Return to top of page · Post #: 3 · Written at 5:31:06 PM on 13 February 2017.
Bushman's Gravatar
 Location: Kempsey, NSW
 Member since 6 December 2016
 Member #: 2019
 Postcount: 33

Hi Carl,

Photo sent to Brad. As this is the first time I have done this I hope I got it right. This photo was done during an overcast day which is good, as it minimises shadowing so the radio should come out reasonably clear.

Pardon the recycle bin under the radio. It was the only thing I had at the time that was high enough to take the photo of the radio.

I hope it meets your request.

Bushman

AWA C48 Radio


 
 Return to top of page · Post #: 4 · Written at 9:35:43 PM on 13 February 2017.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6573

Photo uploaded to Post 3.


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

 
 Return to top of page · Post #: 5 · Written at 3:45:39 AM on 14 February 2017.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1619

Yeah that looks good. Quite often I use our wheelie bins as a work bench for painting and the like. I was hoping your radio was like my coffin radio. I don't have any of the insides and once I finish the box I will be looking for the Insides.


 
 Return to top of page · Post #: 6 · Written at 3:15:47 PM on 14 February 2017.
Robert69's avatar
 Location: Western Victoria, VIC
 Member since 14 November 2009
 Member #: 579
 Postcount: 110

Bushman,

First off, DON'T change the valve bases!! It is better to have a non working original set, than a modified one that does (IMO). After all, how much will you actually use it? I have one of these that I have used the more common B609, B615 or B625 (detector) and B605 (output). At a pinch you might get away with all B609's and the detector. B609's are not hard to find. The HRSA valve bank might have them. You could also use UX201 valves, and use a healthy A supply. DEL series valves are hard to find, but not impossible.

Robert


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
Robert

 
 Return to top of page · Post #: 7 · Written at 12:48:33 PM on 19 February 2017.
Bushman's Gravatar
 Location: Kempsey, NSW
 Member since 6 December 2016
 Member #: 2019
 Postcount: 33

Hi Carl,

What model radio chassis are you looking for? Does it use the same valve arrangement? I could keep an eye out for one.

Hi Robert,

That does give me some hope for finding valves to fit in this radio. What surprised me was that 6 volt filament valves could be used in it. I had not thought it that way as I thought the radio was designed to work with 4 volt filament valves. Isn't it great that some of the radios can have this sort of flexibility.

My original intention was to get the radio (if possible) working with the speaker I have (needs a complete cone replacement, or alternately a replacement speaker). It would give me great satisfaction to restore a radio back to working condition so getting a set of valves would help.

I will try asking the HRSA if the valve bank has the valves.

Thanks for the advice. Gives me a bit more confidence that I will get the desired objective.

Bushman


 
 Return to top of page · Post #: 8 · Written at 3:15:35 PM on 23 February 2017.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1619

Bushman if you unhide your email I will send you a picture


 
 Return to top of page · Post #: 9 · Written at 5:01:57 PM on 23 February 2017.
Bushman's Gravatar
 Location: Kempsey, NSW
 Member since 6 December 2016
 Member #: 2019
 Postcount: 33

Hi Carl,

Email now available.

Bushman


 
 Return to top of page · Post #: 10 · Written at 4:15:28 PM on 30 May 2017.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1619

Hi Bushman . I am sorry I didn't send a photo. Could you please send me a copy of the C54 Schematics as I have access to a Chassis now and would like to study the schematic please.


 
 Return to top of page · Post #: 11 · Written at 5:21:31 PM on 30 May 2017.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4506

"A" voltage is the one to watch some of the Philips ones are 4V some 6V. UX-201-A is 5V and has a very hungry filament.

At the end of the day these are "only triodes" and their gain, if too much can often be curtailed by voltage. There are a couple of those Philips valves here but some have owners.

The biggest issue in these sets other then the odd replaceable coupling transformer, is the grid leak resistor. The bullet headed ones of those have what is best described as an attrition rate. I have one, but many of those can be dismantled and a new resistor adapted.

Marc


 
 Return to top of page · Post #: 12 · Written at 10:03:35 PM on 30 May 2017.
Bushman's Gravatar
 Location: Kempsey, NSW
 Member since 6 December 2016
 Member #: 2019
 Postcount: 33

Hi Carl,

MonochromeTV kindly sent me a link to a .pdf file for AWA Service Data back in January this year, which includes the C54 Radio and a circuit diagram for that model. The file does include other AWA models of that era and it also includes the servicing notes for each model which I find useful. It was suggested that I use the C54 model as a guide to follow the C48 model that I have.

It is good to hear you were able to get a chassis of the model for your restored cabinet.

I have included the link below to assist you. Hope this is acceptable.

http://www.kevinchant.com/uploads/7/1/0/8/7108231/awa_service_data_(1929).pdf


Bushman


 
 Return to top of page · Post #: 13 · Written at 6:50:23 AM on 31 May 2017.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1619

Bushman that's very cool thanks so much.


 
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