On the 6M rig xtal frequencies are:
TX freq / 32.
RX freq - 5.
The book says: "The (RX) crystal oscillates on its third mechanical
harmonic and is ground especially for use in this circuit". The IF is 5MC.
so it is really: (RX freq -5) / 3
Hmm. So do most crystals oscillate on their third harmonic well?
==
On the 2M rig, don't know yet about the architecture.
PJ
From: Geoff <[EMAIL PROTECTED]>
Subject: Re: [AMRadio] Re: The Tucker KW
Patrick Jankowiak wrote:
Well I have worked all day Saturday (just quit now 1AM!!) doing more
cleaning in the lab. I now have the Link 250UFS, the Tucker KW, and
the BTA-250L all next to each other. There are my 6M tranceiver, 80-10
xmtr, and 160M xmtr respectively. The Link is FM, but I bet I could
amplitude modulate it. Not sure if I want to. Is there more activity
on 6M AM or FM?
Not sure, in the North Texas area.
What's the consensus on freq. choices for VHF rigs that are basically
fixed-frequency (meaning they take alot of hassle to re-tune)? What
are the good manners for that? The simplex frequency?
For the VHF rig, and in keeping with staying off of the simplex channel
24/7, build up a xtal switch. If you've got more than one frequency
pair in mind (most repeaters all nowadays use a PL tone for access, so
you'll be better off on simplex with that rig, anyway) you can use the
switch to move to whatever you have available to you. just some xtal
sockets mounted on an aluminum chassis, and a rotary switch. That's how
I've seen it done, even using the old Federal police
transmitter/reciever combos. Back in the late 50's early 60's, those
were some 'boat-anchors'. Seperate transmitter, with a 2E26 in the
final, and a seperate reciever, both on slides in one small(ish) box and
a control head to the dash, with a cable as big as a horse-... well..
you get the idea.
I have a couple of good stable PLL based 0.5-80MHz VFOs (lab gear)
that I could sub for RX and TX crystals if necessary. Talk about
having to keep charts.. No rush though, still alot of cleanout left to
do.
What's the rig use in it? A frequency double-tripler circuit in the
transmitter?
What's the IF freq of the reciever?
Some recievers use a simple tripler scheme. A calculator exercise I
performed with regularity, was the xtal freq of a Regency HR-2A.
Freq - 10.7 (IF) / 3 = Xtal freq
146.64 - 10.7 = 135.94 /3 = 45.3133
so...
146.52 would mean it's need a 45.2733333 xtal or, something that's
going to oscillate at that frequency.
