Author Topic: Roberts R505 - No VHF/FM  (Read 1467 times)

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Turnip

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Roberts R505 - No VHF/FM
« on: April 25, 2017,13:16:40 »
Hi folks,

Got one in for repair and needing a 9v centre negative PS as Roberts are awkward.

AM is fine but not a squeak from FM. Note it uses a Mullard LP1402/2 module incorporating tuning cap for AM and FM and a couple of grounded base transistors for the VHF side.

Any ideas ? - Chris

Attach some info.

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Roberts R505 - No VHF/FM
« on: April 25, 2017,13:16:40 »

mend it

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Re: Roberts R505 - No VHF/FM
« Reply #1 on: April 26, 2017,02:34:52 »
Mullard_LP1180-1402 data all I have

jordan

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Greeting from Slovenia
Jordan Čebron

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Re: Roberts R505 - No VHF/FM
« Reply #2 on: April 26, 2017,03:18:55 »

Turnip

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Re: Roberts R505 - No VHF/FM
« Reply #3 on: April 26, 2017,12:22:09 »
Hi Jordan - Thanks a lot.

Noticed if I tapped the set, FM would appear. Checked around and found the chassis return from the tuner hadn't been soldered to the PBC - Just pushed through the hole, but guess working on and off for some years.

FM reception really good - Chris

Later - Supplied a 9v S/M PS but cust complained it was fine on battery but using the S/M PS caused reception problems I hadn't noticed - Found up a transformer one giving 13v off load - Seems OK.
« Last Edit: April 28, 2017,11:12:19 by Turnip »

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Re: Roberts R505 - No VHF/FM
« Reply #3 on: April 26, 2017,12:22:09 »

 

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