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Ralph Mowery · October 10th 18, 11:09 PM posted to rec.radio.amateur.boatanchors

In article , says...

Reason for asking is that I bought an old receiver that someone has
replaced many of the capacitors. The book says pape capacitors for some
but they have been replaced by the ceramic disk type.

When was it done? If it was done sixty years ago, likely ceramics were the
only alternative you could get. And back then, high voltage NP0s were
available at your local tv repair supplier.
--

This is a hq140 receiver built around 1955.

I have no idea when the capacitors were replaced. I just obtained that
receiver a few months ago and started looking into it. The paper ones
were around .02 and .05 which plenty of ceramic disc were around with
that value during the years. I just thought if the manufactor used paper
instead of ceramic there may be a reason.

I did find the electrolytics were replaced, but I replaced them with the
correct values as instead of the origional 10 and 20 uF values some 100
uF capacitors were used. Some tubes are not recommended to use very
large values for the filters.

Most of my work is with more modern and mostly solid state equipment so
that is the reason for asking about the paper vers ceramic disc. I know
enough about the tubes to do the simple repairs but not from an
engineering point. I have a good assortment of the more modern tublar
type capacitors and could replace the already replaced capacitors if
needed. To me at frequencies of audio and lower unless dealing with
critical frequency circuits , a capacitor is a capacitor if the UF and
voltage is in range, but I could be educated on that. Now, RF and
critical frequency circuits are totally different.