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 Return to top of page · Post #: 1 · Written at 1:27:10 AM on 26 July 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2201

Got a question. I am repairing a classic radio gram.
I had a dead short circuit when I connected the record player. Now nothing works. The dial lights do not light up. Is it possible that the dial lights are in series with the heaters.
It's not likely that the transformer is blown as it tripped the protection circuit in my fuse box.
I haven't looked any further as I have been crook. The radio worked perfectly before I hooked the player up.


 
 Return to top of page · Post #: 2 · Written at 10:55:57 AM on 26 July 2019.
Irext's avatar
 Location: Werribee South, VIC
 Member since 30 September 2016
 Member #: 1981
 Postcount: 485

I assume you mean a 240V dead short?
Should be easy enough to trace with a multimeter.
If it's the turntable motor shorted it wouldn't be connected to the transformer secondary any way.
Does it have a mains fuse? (a lot of vintage gear doesn't).
Do you have a circuit?


 
 Return to top of page · Post #: 3 · Written at 5:14:04 PM on 26 July 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6828

Is it possible that the dial lights are in series with the heaters.

If it's a transformer set then the dial lights are most likely in parallel with the heaters on the 6.3V AC winding.

Should be easy enough to trace with a multimeter

This.


 
 Return to top of page · Post #: 4 · Written at 11:05:36 PM on 29 July 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2201

Ok we found the issue. You would not read about it!.Yes it was me that stupidly hooked up a record player with a dead short. But it didn't blow the transformer, it didn't blow the switch, what it did blow was a factory dry joint on the back of the switch.

It is now working better than new.


 
 Return to top of page · Post #: 5 · Written at 12:08:22 AM on 30 July 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5492

It does pay to check a lot of that sort of stuff if its new to you: Its amazing what you find wrong, before it becomes an issue.

Its more common to find a turntable motor in European sets tapped off a transformer, or ballast. So it is less likely to be like that here, substantially reducing any risk to the transformer.


 
 Return to top of page · Post #: 6 · Written at 8:11:35 PM on 30 July 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2201

Now I got to work out how to get the changer playing well. I got it to play at 78 but couldn't get it to change speeds.


 
 Return to top of page · Post #: 7 · Written at 8:29:38 PM on 30 July 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5492

Invariably if it has not been serviced from the day it was made, the grease soap has probably dried out & its gummed up. That's the first thing took at.

Philips used Shell Alvania Grease. Do not use engine oil.


 
 Return to top of page · Post #: 8 · Written at 9:34:38 PM on 6 August 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2201

A question. I nearly have this complete. I have installed a working Garrard Turntable . But I am told because it's a crystal pick up that I can install a 1-2 meg resistor to increase the volume. Where should that be placed please?


 
 Return to top of page · Post #: 9 · Written at 6:13:43 PM on 10 August 2019.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2549

Re the resistor - does it work as is? Then leave it alone!

I can't see how adding a resistor around the cartridge would do anything other than decrease the volume.


 
 Return to top of page · Post #: 10 · Written at 8:29:33 PM on 10 August 2019.
Gandhn's Gravatar
 Location: Cameron Park, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 422

We really need a circuit to see what load resistance the crystal is connected to. I recall that a crystal likes a load of at least 1 megohm so maybe replace it if it much lower than this. Always with the proviso that it won't affect something else.
Harold


 
 Return to top of page · Post #: 11 · Written at 10:15:18 PM on 10 August 2019.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2549

The load impedance affects the equalisation from a crystal or ceramic cartridge. A higher impedance will extend the bass response, lower rolls it off but lifts the high frequencies.


 
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