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The Murphy CBH1500 Homebase was a cheap Cb from the 80's. I remember my
one I bought new from Hewards Homestores in Birmingham in 1985 costing me
in the region of £50 which, for a new homebase was a very good price.
They were by no means the best.. they suffered from close broadband (not as
bad as some though) and the squelch was "clunky" when it dropped in and out
(noticeable at night when radio was turned down) and if you listened closely
there was some mains hum due to the manufacturers not using a shielded
transformer but other than that... not bad.
For some reason they were very popular and even I still have mine. True it has
mid and splits + a k-tone bleep and has had the transformer removed (now runs
off 12v) and is "cybernet" wired, so its by no means standard  but I became
attached to it and with all the rigs ive bought and sold in the past..I kept this one.
This page may help you understand the radio better
The first thing I normally do when I get one of these radios is to re-wire the back of the mic socket so its "cybernet" and more mic friendly than it would
otherwise be as its original wiring is a bit unique. Basically it is cybernet but 90 degrees out of sync. The two pictures below show you what to do..
Click for Large Picture
-------------Click the above or below for a larger pic -----------
Click for a Larger Pic
Click for a Larger Picture
With these radio's also, the meter plate comes loose and jams the
needles. If this happens a strip down of the front panel is needed (not
difficult but takes time) and the meter removing, opening carefully and
the plate glueing back down. When this has been re-assembled and
fitted back in situ, I  move the meter bulb and fit it to the top of the
meter. That way the meter lights a whole lot better. The original wires
should just stretch enough to do this.

Then I take a red and black wire from the 12v input part of the board
and wire them to the back panel. This allows you to run small
accessories off the built in PSU or, it allows you to externally power the
radio via a 12vDC supply... ie in the car or a battery if where you live is
prone to power cuts.
CB Radio History from its early days
CB Radio Repairers in the UK
The inner workings of the 1500 Homebase
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