Re: S-40A Question

Hello Richard:

I think I know what the problem is - but this is only a guess. Both you and
I have S-40A receivers where the bandspread capacitor has the lockout pin on
the wrong side of the retaining plate. They both appear to be factory jobs,
and the problem is that the receiver cannot be calibrated correctly.

In all cases, the restringing technique is the same for the S-40, the S-40A
and the S-40B.

I think the only logical conclusion is that Hallicrafters received a number
of capacitors that were manufactured defectively. They may have made them
themselves, which means that they would waste the money in remaking them.
Or, if a sub-contractor did it, they may have received a substantial price
break. In either case, Hallicrafters made the conscious decision to use
these defective capacitors and save money.

By stringing these capcaitors like you suggest, everything will operate
normally. And, there will not be a problem for years - or ever. I suspect
that in both of our receivers, the bandspread string broke and required
restringing. In both cases, the restringer strung it just as the service
instructions specified - which is why they do not work correctly. Since the
original change could not be observed (because the original string was
broken), the restringer would not know of the problem.

I think your solution is the only reasonable one. I suppose we should put a
note inside the receiver, so that in 30 years, when the string breaks again,
the same issue will not arise once more.

Perhaps we could put our S-40A receivers on eBay and advertise them as
unique or rare.

Glad you posted this, as I was beginning to think I had simply been working
on old radios far too long.

73, Colin K7FM


.

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