Here is a review of a frequency counter kit copied from Handiham.

The ScQRPions Stinger Singer Frequency Counter
A review by Tom Fowle, WA6IVG
Smith-Kettlewell Eye Research Institute

Do you know where you are on the bands at all times? Are you one of
the many blind hams who doesn't have a talking rig? Do you get lost
on your 2 meter H.T.? This new Morse code output 180 MHz frequency
counter kit may be just the thing. Available from a group of QRP
enthusiasts in Arizona called the "Scqrpions" (Like scorpions
with "QRP" in the middle) the so-called "stinger singer" is a $20.00,
that's correct only twenty bucks, counter that fits in an Altoids
can, runs on a 9 volt battery or external power and can count up to
over 50 MHz as shipped and over 150 MHz with an inexpensive chip
change. Frequency is read out in Morse code at two speeds, "fast and
slow" and with several different resolutions depending on your needs.
With a wire plugged into the phone jack input, and wrapped round the
rubber ducky of your 2 meter H.T. you can read the transmit frequency
using less than a watt of output and a 1 second transmission.
With a simple resistive "pad" or divider, you can read the frequency
of your H.F. rig again with only a 1 second transmission.
The counter has only 2 controls, an on/off switch and one push
button. Various modes of operation, code speed and readout
resolution, are selected by pressing and holding the button. A
frequency measurement and readout happen every time you push and
release the button. The "speaker" is a "piezoelectric" disc which is
glued to the metal lid of the Altoids can. It produces a good clear
loud Morse tone at about 800 Hz, and, I think, could be readily felt
by a deaf-blind ham. Limitations? Yes, it won't go up to UHF, and it
won't read below about 500KHz, so you can't read the "CTCSS" tone of
that unfamiliar repeater. It needs about 100 Millivolts of input, so
it may require a little fiddling in different H.F. applications to
get it enough signal and not too much to work properly.
These are very unimportant limitations considering what you get.
The kit is relatively easy to build for anybody with basic P.C. board
soldering experience. If there is substantial interest among blind
hams who want kits and can't get friends to build them, we here at
Smith-Kettlewell Rehab Engineering Center may consider doing a set of
Braille and tactile instructions allowing a blind technician to build
the kit. This is an inexpensive and very useful instrument in a world
where accessibility usually comes at a high price if at all.
I've been dealing with the problems related to being a blind ham for
over 40 years, and this is one of the "coolest" gadgets I've ever
seen. I strongly encourage anybody with the slightest interest to
grab up one of these kits and get it built. Your Morse numbers skills
will get good real quick, and it's fun. And anybody who whines that
they make cheap talking clocks so why don't they make cheap talking
everything will get the idiot of the day award and be promptly
ignored.

Blurb from the web site with ordering information:
http://www.extremezone.com/~nk7m/cwafc.htm
Az ScQRPions Stinger Singer A CW Audible Frequency Counter: The
ScQRPions Stinger Singer Frequency Counter is now available. Cost is
$20.00 per kit. Please send a check for this amount, made out to Bob
Hightower, and send to Bob Hightower, 1905 N. Pennington Dr.,
Chandler, AZ 85224-2632 to order. PLEASE include a return mailing
label with your order. If you have a Pay Pal account, you may order
from there. Please indicate in memo field that you are ordering the
SSS kit.

Tom Fowle, WA6IVG
Embedded Systems Developer/ Rehab engineer Rehabilitation Engineering
Research Center
The Smith-Kettlewell Eye Research Institute
2318 Fillmore St. San Francisco, CA 94115
415-345-2123 (Voice)
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