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 Peter Pan radiogram mr1317
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 Return to top of page · Post #: 1 · Written at 10:39:00 PM on 1 August 2016.
Thomasmitch's Gravatar
 Location: Warrnambool, VIC
 Member since 16 January 2016
 Member #: 1858
 Postcount: 19

Hey there recently obtained a peterpan radiogram the amplifier it's self is in fairly good condition the
Capacitors aren't leaking etc
There is currently no radio but will play a record but only low volume
I've cleaned up all the connections between the turntable and the amp
But no change one thing I did notice the valves were getting really hot
One large valve next to the transformers which I can't identify due to faded markings has
A small amount of blue glowing around its anodes.
Pictures to come any ideas and information would be great


 
 Return to top of page · Post #: 2 · Written at 10:49:56 PM on 1 August 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6014

I did notice the valves were getting really hot. One large valve next to the transformers which I can't identify due to faded markings has
A small amount of blue glowing around its anodes.


The valve glowing blue will likely be the rectifier (5Y3). These sound like the classic symptoms of a short circuit the B+ supply making the valves work too hard -- especially so if the anodes are red.

Don't switch it on again unless you want to be up for a replacement of the power transformer (if you can even find one).

Do a re-cap.


 
 Return to top of page · Post #: 3 · Written at 12:14:21 AM on 2 August 2016.
Thomasmitch's Gravatar
 Location: Warrnambool, VIC
 Member since 16 January 2016
 Member #: 1858
 Postcount: 19

Hey thanks for your message
I will start with the capacitors first one I've seen with the mustard capacitors and not the paper ones


 
 Return to top of page · Post #: 4 · Written at 12:18:11 AM on 2 August 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6014

If you unhide your email address (via Control Panel) I'll send you the model MR schematic. Not sure about the 1317 bit, but this should be useful.


 
 Return to top of page · Post #: 5 · Written at 12:21:40 AM on 2 August 2016.
Thomasmitch's Gravatar
 Location: Warrnambool, VIC
 Member since 16 January 2016
 Member #: 1858
 Postcount: 19

That would be great !! Have changed my email privacy.
Thanks heaps


 
 Return to top of page · Post #: 6 · Written at 12:31:27 AM on 2 August 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6014

Okay, sent.


 
 Return to top of page · Post #: 7 · Written at 12:41:54 AM on 2 August 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4348

Pale blue around the outside of the anodes can also indicate its gassy. Red plates, definite issues.

And how pray tell did you determine that the capacitors were not leaking? There are two ways Electrolytics leak & one can destroy rectifiers & transformers. The only way that you can determine if a non polarised cap is leaking is to take it out of circuit & high voltage test it, with an insulation tester, or capacitor leakage tester. If it is a "waxed paper" type, it will be leaking: You just replace them, not waste time testing them.

The fact that the radio will not play and it has low volume says serious issues. Remove the chassis & photograph inside of the pan (in focus & sharp) so we can see what is in there.

An understanding of valves will reveal that rectifier & output valves put out more than enough heat to burn fingers & fry eggs.

As above, do not bother to turn it on again and the record changer / turntable is also going to need servicing.

Marc


 
 Return to top of page · Post #: 8 · Written at 1:07:44 AM on 2 August 2016.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1576

The actual cost of replacing the capacitors is so negligible that it really is a waste of time testing them. Replace all the non mustard caps then and all associated resistors then test it through a variac if you have one .


 
 Return to top of page · Post #: 9 · Written at 1:24:00 AM on 2 August 2016.
Thomasmitch's Gravatar
 Location: Warrnambool, VIC
 Member since 16 January 2016
 Member #: 1858
 Postcount: 19

There is only really the mustard caps in it.
When I said before there was no leaking caps I meant the paper ones that are there aren't leaking contents.


 
 Return to top of page · Post #: 10 · Written at 1:32:08 AM on 2 August 2016.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1576

They may not be leaking their contents but believe us , They need to be replaced. The MICA caps probably wont need replacing.


 
 Return to top of page · Post #: 11 · Written at 1:37:52 AM on 2 August 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6014

the paper ones that are there aren't leaking contents

They are probably 50 years old or more. Paper caps use by date was decades ago, regardless of how they appear externally.

Also, any old electros are dynamite -- literally, as they can explode. The filter and reservoir caps in power supplies are notorious for destroying components and in the worst cases starting fires.

As a general principle, we would never even consider powering up such a set without having dealt with the caps (and resistors as necessary) and also looking for shorts, etc.


 
 Return to top of page · Post #: 12 · Written at 10:10:08 AM on 2 August 2016.
Thomasmitch's Gravatar
 Location: Warrnambool, VIC
 Member since 16 January 2016
 Member #: 1858
 Postcount: 19

Thanks for all your comments I will email the pictures to be uploaded today. I am excited to get this one up and running properly . I have already started to replace the rubber insulated wires and have a list of the caps I need to get in town


 
 Return to top of page · Post #: 13 · Written at 12:09:06 PM on 2 August 2016.
Sue's avatar
 Sue
 Location: Daylesford, VIC
 Member since 13 January 2011
 Member #: 809
 Postcount: 311

If the radiogram really has Philips polyester ''mustard caps", those will probably be OK. I've heard that yellow Ducon polys are also reliable.


 
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