Re: 49Mhz to 6Meters conversion?


From: Daniel C Winkler (
Date: Mon Jul 14 1997 - 09:07:19 EDT

Hi Gang,

>Radio Shack ...selling a 49Mhz walkie-talkie for about $5.
>... any plans fo modifying these to work on 6 meters?
>... cw built-in...

I don't think these are the same units Dana spoke of in his
post (7-9-97) ...(YES, I am that far behind on my mail!).

I have a pair of similar units from RS from a year ago.
I got curious, so I just now took one apart.

Plastic case 6 x 2.5 x 1.5 inches w/ 9v battery compartment...
case held together by single screw and a little gum (really).
Well, there are little plastic fingers to help.
PC board held in place by another single screw. Speaker is
glued in. Antenna is a 9" ducky... looks like it is a 9" length
of door spring with shrink wrap over most of it!

There are:
  3 transistors
 1 transformer
 3 switches (sorta...if you count a piece of tin can bent up over but not
touching a longish rivet a switch!)(that's the "key")
 13 resistors
  8 ceramic capacitors
  3 electrolytics
  2 coils (To quote one of the masters {the good Rev.}{you gotta read
with a British accent!} "...look inside the radio, and if it has a lot
of coils, then
you know it is a good radio.")
  1 crystal
  1 pc board 3.5 x 2 inches, with .75 inch hole in it (for speaker)

These things are AM modulated crystal oscillators. The receiver is a
super-regen, and you wouldn't believe the RUSH it gives out on
receive. There is no volume control, only on/off. The "cw"
is mcw, achieved by introducing feedback into the audio amp.


It is about as minimalist as you can get and be voice. It
does work. Range abt 1/4 mile (I can shout as far).

I, too, bought them with 6m conversion in mind, but after looking
them over, I decided it would be better to start from scratch.

However, look at it another way. For $5 you get a door spring.
And an ok case with battery compartment. And a little speaker
built in (VERY built in). And a crystal (49.860). And a transformer.
The rest of the parts are probably not worth saving.

So you could keep the crystal and use it for the XO for a superhet
(it's an overtone xtal, so it won't warp much- not much of a VXO-
you are stuck on one frequency!) with a 455 kHz IF (use one of those
Murrata ceramic filters from Digikey or Mouser)- puts you at 50.315.
Buy a crystal for 50.315. (About $15) Run AM (you are above 50.1,
so anything goes, as far as FCC is concerned...)

With a little work you could stuff it all back into that case...

A lotta work for little return, I think. But the parts are probably
worth close to that $5 price, *if* you can use them.

Dan Winkler N7IVR Seattle WA

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