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 PHILIPS MODEL 124 SCHEMATIC
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 Return to top of page · Post #: 1 · Written at 9:23:43 AM on 8 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Hey I was lucky enough to get the parts to complete this set on the weekend and it works reasonably well.
Does anyone here have the service manual for this one as I need a list of the resistors so I can attempt a check. Its still a bit low in volume. Email is open. Thanks guys.


 
 Return to top of page · Post #: 2 · Written at 7:13:12 PM on 8 May 2023.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6720

 
 Return to top of page · Post #: 3 · Written at 8:46:16 PM on 8 May 2023.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

- removed incorrect statement -


 
 Return to top of page · Post #: 4 · Written at 10:01:46 PM on 8 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

When I get the time I will pick through all the resistors. It picked up quite a bit when I recapped it but still low volume.


 
 Return to top of page · Post #: 5 · Written at 10:37:22 AM on 9 May 2023.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

2nd attempt. Expediency and efficiency and avoiding potentially damaging rework demand that as you consign waxed paper & old electrolytic caps to bin. One does their best to to test the resistances as you go. That also applies to any Mica or ceramic cap with an end out of circuit whereupon you insulation test it.

The greatest cause of "deaf" sets is alignment. This is recommended by most manufacturers, should you tamper, or replace with anything in the RF /IF you re-align. Some Philips IF cans cannot be adjusted.

Marc


 
 Return to top of page · Post #: 6 · Written at 8:01:34 AM on 10 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Marcc in this set the chassis is fairly large and open. With the resistors can I test them in circuit? I'm a bit time poor at the moment as I have multiple x 60 hour weeks coming up ( does it ever end? ). I just intend testing every one from top to bottom and if I find a few values that don't exist in the schematics ( more than 20%) I will investigate and replace. I know there are a few 50k and 1 Meg in there.


 
 Return to top of page · Post #: 7 · Written at 9:10:04 AM on 10 May 2023.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

Some resistors like grid & plate give a reasonable reading. Generalising: If a resistor reads high in circuit it needs further attention.

The highest attrition rate are 100K, 500K & 50K, plate resistors on 2nd detector 1st AF and output tube grid one resistors. I use 10% for out of spec. but the bad ones are usually worse.

If you want to kill time (which will end up killing you) Farming tends to be 24/7 currently here after the back gets mobile the day all week will start before 09:00hrs and will often end after 00:00 Hrs.

Watch the Philips transformers. I have seen several in that era have windings move out from the wrap: On the sides. do not touch them with your greasy fingers; alive, or dead.


 
 Return to top of page · Post #: 8 · Written at 7:48:04 AM on 11 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Ok I have the schematics in front of me! I have noticed there are no resistors above 1 watt. Does it matter if I use all 2 watt. I note that some are quarter watt and half watt.


 
 Return to top of page · Post #: 9 · Written at 7:55:44 AM on 11 May 2023.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6720

Does it matter if I use all 2 watt.

No problem. If they fit in the space available all is good.

Side note: the larger the resistor the better the handling of high voltage due to wider separation of the connections. Oftentimes, using 1 watt in place of half watt or quarter watt can avoid flash-over.


 
 Return to top of page · Post #: 10 · Written at 10:32:52 AM on 11 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

GTC these 2 watt resistors are heaps smaller than the originals.
When running the set I'm getting strong AM but nothing in shortwave. I'm guessing I may have a open circuit antenna coil or oscillator coil ( may not be a issue ) or maybe a resistor so which one should I look for?
Im at my work and wont be seriously looking at the set for a week.


 
 Return to top of page · Post #: 11 · Written at 2:31:16 PM on 11 May 2023.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6720

these 2 watt resistors are heaps smaller than the originals.

For valve gear such as radios and amplifiers, I use carbon resistors which are larger than modern metal film resistors.

Regardless, you can still use 2 watt in lieu of the lower wattages.

I'm getting strong AM but nothing in shortwave.

First thing to check is the band change switch. I've been fooled by non-obvious problems with that.


 
 Return to top of page · Post #: 12 · Written at 8:17:47 PM on 11 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

GTC
You were correct ! The band change switch was dirty. I checked it tonight and even though low volume it was picking up very strongly in shortwave Smile


 
 Return to top of page · Post #: 13 · Written at 8:35:12 AM on 24 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

I have had some sort of success with this set. Its performance has improved significantly since changing out some out of spec resistors. I havent as yet changed out the electrolytics ( havent had time ) .
My question is this! The choke is connected to the positive of one of the electrolytics which of cause is negative to ground ! If that electro is leaking can that have a effect on the B plus ? Its still lower volume and slightly distorted.
Don't get me wrong I'm going to change them out this weekend as I may have 3 days off Smile .
I am just thinking out loud at the moment as I'm at my workplace and the set of cause is not here in front of me.


 
 Return to top of page · Post #: 14 · Written at 2:55:10 PM on 24 May 2023.
Irext's avatar
 Location: Werribee South, VIC
 Member since 30 September 2016
 Member #: 1981
 Postcount: 482

Might need an I.F. alignment.
I remember having a set many years ago which was struggling with volume and an I.F alignment brought it back to life.


 
 Return to top of page · Post #: 15 · Written at 2:25:30 PM on 29 May 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

I have replaced many out of tolerance resistors but it's still distorted! The 500 k volume pott measures at 275 k. Could this be the issue?


 
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