JIMMIE wrote:
On Mar 20, 6:47 pm, ken scharf wrote:
JIMMIE wrote:
On Mar 18, 9:24 pm, Robert casey wrote:
The design used plug-in coils for the osc and rf stages, and
they were double conversion designs, with a first IF of
1600 kc and a second IF of either 100 kc or 85 kc (when
using surplus ARC-5 IFTs.) The 1800 mc xtal you bought
your dad was used for the second coversion osc. to convert
the 1600 kc IF down to 100 kc. Many hams deviated from
the exact original IF frequencies (i.e. strong local BC
station on 1600 kc) which might explain why the xtal
was chosen for 1800 kc instead of 1500 or 1700.
We have a local mid power station at 1600KHz, WWRL, at my parents' house,
so my father might have wanted to avoid problems with it.
His radio had a bandswitch instead of plug in coils, and he'd receive
various broadcast SW stations. He wasn't a ham at the time just yet.
I had a friend who was a retired engineer with GE turned TV tech who
built
one with a band switch and he later modified it to
be more of a general purpose SW receiver. His name was Olin Griggs.
Jimmie.
I once saw an article in 73 magazine showing a HB receiver that used a
re-worked turret tv tuner as a band switch. The coils were re-wound
onto the original forms, but some have just replaced the forms with some
of the smaller sized toroid cores. I have a bunch of old tv tuners in
the junk box, but over the years the contacts have gone bad and now show
a high resistance. Maybe they could be cleaned up, but it no longer
seems worth the effort. My new idea is to use miniature relays to
switch the circuits. I recently found nearly a gross of small relays
for free so why not?- Hide quoted text -

- Show quoted text -

I tried the TV tuner trick one time and it didnt work well at all.
Most tuners are tossed because the contacts fail. ...


Not really. Back then TVs were often tossed because the flyback xfmr had
blown and repair was deemed uneconomical. Or someone said that because
in reality they wanted that brand spanking new set that was one sale.

But this is so long ago that if there's any left the contacts will have
corrodes away.

[...]

--
73, Joerg