RadioBanter - View Single Post - Ameco AC-1 problem

April 3rd 04, 05:41 AM

in article ,
Paul_Morphy at wrote on 4/2/04 19:37:

"Uwe" wrote in message
...

By the way, I see suggestions how to just "stretch" crystal controlled
oscillators a bit by adding a suitable coil and capacitor in series with
the
crystal. Has anybody tried that with the AC-1??
Would be nice to be able to get out of the ways of some of the big power
guys.
Any suggestion would be welcome.

An rf choke or variable inductor of between 7 and 20 uH in series with a
variable cap of about 200 pF in series with a crystal, will pull the
frequency. It's called a variable crystal oscillator or VXO. You're probably
using FT-243 crystals, though, and they don't pull very far.

I have to say this again: Time to put this thing on the shelf. For the time
and trouble you are putting into it you could build a solid-state rig that
would put out as much power, have a VFO and not contain life-threatening
voltages.

73,

"PM"

Thank you Paul, since I have a crystal socket on the front of the little box
it ought to relatively simple to try out this scheme and see if I can't get
a "range" out of this one frequency device.
And yes you are right, I have a few FT 243 but others are on order.

It is my experience that whatever I do around the crystal it stops it from
oscillating but I will try your suggestion nevertheless.

As to high voltages I grew up in Europe where I got used to (and sometimes
shocked by) 220V and now I can't let go ...

Paul, your concern for a new ham is very much appreciated, but ever since I
wanted to be a ham I wanted to know code and I wanted to build my own gear,
preferably tube gear.
It gets cold in Maine and these at least warm your hands in between QSO's.
I will probably never own an SSB or a phone radio and as somebody mentioned
here, for communication we have other solutions. For me being a new ham
opens a world of learning and tinkering possibilities with the side effect
of being able to communicate with others via code.

And I think I can learn a whole lot by working on this transmitter. And I
will need all the learning I can get because someone mentioned a different,
slightly more sophisticated tube transmitter using two 807's in the final. I
would love to build that and appreciate more info on the device.

And Paul, lest you get the impression I hate silicon, I just finished a
Rockmite-very cute.

Thanks again and keep the advice and help coming.

Greetings from Maine

Uwe