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simonjp · 4th Oct 2018, 3:14 pm

Hi

I recently acquired the 1772. The op said that it no longer worked. He had hardly used it.

I have a couple of questions.

I have the service manual.

The set appears muted in so far as there is no audio whatsoever, and after sticking a piece of wire into the ant jack, no signals either.

All voltages according to the onboard voltmeter seem normal.

I seem to have 68Mhz on the rear bnc instead of 34Mhz.

Should I assume that if any or all of the internal loops dont meet their respective conditions that the set defaults to a muted state?

It doesn't say anything in the manual. Maybe my question is too obvious.

Before I dig deep, I thought I would treat the radio to new filter caps, and get rid of as many tants as I can find.

But I have had a nasty surprise whilst trying to find suitable alternatives.

Each filter cap has a ripple current of between 7 and 8amps. I assume that they are long life too.
But even when searching for the first one which is 10,000uf at 16V ripple current 7.9A, the cost of such a beast is £10 upwards.

I anticipate that the ripple current marked on the cap is well above what is expected.

Does anyone have any personal experience of re-capping the racal?

Also, any leads to replacement slide switches that mount on the rear panel? They seem to have 25mm fixing centres.

Is there any experienced RACAL service engineers near to me ( Hailsham ) east sussex?

4th Oct 2018, 3:14 pm	#1
simonjp Tetrode Join Date: Sep 2014 Location: Lewes, East Sussex, UK. Posts: 55	Racal RA1772 help Hi I recently acquired the 1772. The op said that it no longer worked. He had hardly used it. I have a couple of questions. I have the service manual. The set appears muted in so far as there is no audio whatsoever, and after sticking a piece of wire into the ant jack, no signals either. All voltages according to the onboard voltmeter seem normal. I seem to have 68Mhz on the rear bnc instead of 34Mhz. Should I assume that if any or all of the internal loops dont meet their respective conditions that the set defaults to a muted state? It doesn't say anything in the manual. Maybe my question is too obvious. Before I dig deep, I thought I would treat the radio to new filter caps, and get rid of as many tants as I can find. But I have had a nasty surprise whilst trying to find suitable alternatives. Each filter cap has a ripple current of between 7 and 8amps. I assume that they are long life too. But even when searching for the first one which is 10,000uf at 16V ripple current 7.9A, the cost of such a beast is £10 upwards. I anticipate that the ripple current marked on the cap is well above what is expected. Does anyone have any personal experience of re-capping the racal? Also, any leads to replacement slide switches that mount on the rear panel? They seem to have 25mm fixing centres. Is there any experienced RACAL service engineers near to me ( Hailsham ) east sussex?