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 Quiet Peal, possibly suffering loss of induction in the I.F. section.
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 Return to top of page · Post #: 1 · Written at 1:37:31 PM on 21 July 2016.
JamieLee's Gravatar
 Location: Clare, SA
 Member since 27 March 2016
 Member #: 1894
 Postcount: 501

I have a Peal, 1947 model with valve line-up of 6G8G, 6J8G, 6V6G 6X5G it's apparently a model 458 with the B408 chassis.
Kevin Chant has been helpful and suggested the reason it is "Quiet", (low volume) is due to loss of inductance in the I.F. section, as he has had the same issue with this particular model and it is apparently common for these sets.
I am wondering if anybody else has dealt with and/ or resolved this problem and managed to get the radio loud again, I wonder could a bad resistor possibly cause this. All caps have been done, but the resistors appear original and I have a schematic so I am able to get the values and test them, which is my next step.
Any comments appreciated.
Cheers.


 
 Return to top of page · Post #: 2 · Written at 2:03:58 PM on 21 July 2016.
Redxm's avatar
 Location: Tamworth, NSW
 Member since 6 April 2012
 Member #: 1126
 Postcount: 436

Resistors are much easier to check while you have the caps disconnected, easy enough to lift one end while you have the iron in there.
1 meg or higher are an instant target for me, but all sorts of types seem to go high. 10% tolerance is a good figure to work with.

Make sure the IF's haven't gone open circuit. Does the radio perform normally apart from low volume? Some IF cans have caps inside them, but failure rate is not that high. 1947 model may still have the body-end-dot resistors

Ben


 
 Return to top of page · Post #: 3 · Written at 2:39:10 PM on 21 July 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1094

Looks like it's a 4-valve set, which means it's missing the audio preamp stage. So it isn't going to make a lot of volume anyway. Perhaps it's operating normally.

Or maybe you left one out...


 
 Return to top of page · Post #: 4 · Written at 8:15:01 PM on 21 July 2016.
JamieLee's Gravatar
 Location: Clare, SA
 Member since 27 March 2016
 Member #: 1894
 Postcount: 501

It's definitely a 4 valve set, not sure what you mean by "Body end dot" but maybe because the resistors are strange, normal background colour, but with a thick yellow band and silver dot one end?
It get's great reception and acceptable volume with ABC and stronger stations but our favourite rock'n roll stations, Adelaide's 1323 and 5CS (Port Pirie) both over 100k's from here in Clare... a bit quiet, was my gift to my wife as a kitchen radio and was good when the lad or anybody wanted to watch tv or play games in the lounge area, they wouldn't be disturbed and the music in the kitchen is listenable, The consoles in the lounge both can blast up a storm when we want volume! However I recently acquired an Astor (5 valve) (also in the kitchen) And the astor really rocks, ir's loud and strong performing and quiet with interference, and has me looking at the Peal wondering if it's under-performing and I have learned that these Peals are prone to this quietness, IF inductance problem, It makes sense that a newer 5 valve model would have a bit more guts, but with the bigger valves the Peal I would expect to be a bit louder... I'm going to order some resistors from the schematic nd pop them in and see what happens, check the IF coil too!
Thanks' guys.


 
 Return to top of page · Post #: 5 · Written at 9:18:38 PM on 21 July 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1094

not sure what you mean by "Body end dot"

In the old days the resistors were painted a certain colour, then one end was painted another colour and a stripe added in the middle.

See this link for an example:

http://www.radioremembered.org/rescode.htm.


 
 Return to top of page · Post #: 6 · Written at 9:32:31 PM on 21 July 2016.
JamieLee's Gravatar
 Location: Clare, SA
 Member since 27 March 2016
 Member #: 1894
 Postcount: 501

Thank you Robbbert!
That link is great!


 
 Return to top of page · Post #: 7 · Written at 12:19:54 AM on 22 July 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3791

I will never replace capacitors without checking the resistors as I go. The grid resistors on 6V6 have an attrition rate & rarely are they in spec. and the plate resistor on Det is audio (6G8) is a common failure in any set. With four valves it is liable to be reflex set.

Before jumping to conclusions go back & sort out the resistors. 6J8 loves voltage and any failed resistors there will reduce its performance. If you disturb the RF section then the set needs to be aligned:Most manufactures suggest that when the RF section has had parts replaced Bad alignment causes many sets to be " deaf".

If the IF transformer do not align only then do you have an issue: Not before. Do not use too much signal (12uV at terminal).or the AGC (where fitted) will cut-in & you will never get it right

Marc


 
 Return to top of page · Post #: 8 · Written at 8:39:09 AM on 22 July 2016.
Flakes's avatar
 Location: Adelaide, SA
 Member since 27 February 2010
 Member #: 630
 Postcount: 392

Hi Jamie

I am in the great state of SA as well. On a random inside wire antenna Cruse 1323 is allot lower than the 891 ABC. I live in the southern Suburbs and get a extremely strong transmission from the Pimpala ABC 50KW transmitter. The transmitter for Cruse 1323 is only about 3KW.

http://wikimapia.org/1634577/Pimpala-Transmitting-Station

Once you are sure that the radio doesn't have an electrical fault as Marc and others have suggested, Use an external antenna as the Cruse signal is not all that strong and see what the AGC is doing.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
Valve radios, They just don't make them like they used to

 
 Return to top of page · Post #: 9 · Written at 3:14:55 PM on 22 July 2016.
JamieLee's Gravatar
 Location: Clare, SA
 Member since 27 March 2016
 Member #: 1894
 Postcount: 501

Hi Flakes, yes that ABC station cut's through loud and clear on all of my radios, but with only 3kW, that explains the quietness of 1323! I use a 30metre wire antenna and all my radio's alligator clip onto that except my Astor and the two little Kreisler's, which have ferrite rods and pick up well.

Thanks Marcc, yes if they have an attrition rate, I would be surprised if they are not crook, so will replace anyway, I'm sure it will be a happier radio with new resistors.

I think from now on I'll make a habit of checking them when re-capping. Makes good sense.

Thanks guys!


 
 Return to top of page · Post #: 10 · Written at 10:49:04 PM on 22 July 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3791

Whilst it may take all of the fun out of fault finding, there is no difference here, in the procedure for a commercial fix or any other.

It is a pointless exercise fault finding a radio that has wax paper caps & old electrolytics. Several things can & should be checked, as part of assessing if it is a viable repair. If the thing comes in barely working that saves a lot of testing & repair is normally ruthlessly fast.

If I have a resistor out of circuit; a Mica, or Ceramic cap, I will check both: One resistance the other leakage. That saves rework and extra risk. Even if it is badly, the set will, over 95% of the time fire up & you can then de-bug it and realign it.

That may sound like a bit of work but in the fact that you rarely have to fix anything complex afterwards, it saves time & money with a commercial fix.

Of course about two or three in a hundred will be an absolute swine, especially if some hacker has been in it. I have a classic one of those at the moment, which I am trying to get time to get at. I am sure the Monkey that got at it has applied 240V not 115V, as both IF transformers were open on the plate winding. Something I have not seen on a local radio.

Marc


 
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