hmmm. well, a simple pre-amp wouldn't be hard. its just a simple emitter-follower (high impedance input and about 3 or 4 parts).

DE n7zzt Eric

On Nov 11, 2015, at 10:35 PM, Tom Fowle wrote:

> Eric
> If you're referring to the "ADAM", as you say it takes several volts of R.F.
> We suggested improvements, but they weren't interested.
> 
> Without a pre-amp, a 555 needs about 1/3Rd of VCC to shift it's freq.
> tom WA6IVG
> 
> On Wed, Nov 11, 2015 at 09:55:54PM -0700, Eric Oyen wrote:
>> actually, there is another design that will work. it just requires a 555 =
>> timer IC, about 10 or 11 parts and a 9 volt battery. One of the parts =
>> can be a piezon-electric transducer. There is a audio watt meter that =
>> uses something like this. However, its design is not sensitive enough to =
>> function as a field strength meter. I might get hold of the maker of it =
>> and suggest some designs he might look at.
>> 
>> DE n7zzt Eric
>> 
>> On Nov 11, 2015, at 8:48 PM, Tom Fowle wrote:
>> 
>>> Ed,
>>> Yeah I know you don't want to build, but since I don't know of a =
>> commercial
>>> device, there is at least one design in the
>>> Smith-Kettlewell Technical File
>>> http://legacy.ski.org/rehab/sktf/index.html
>>> It's based on a very old circuit from the braille technical press days
>>> called "audio gimmick"
>>> two transistors a simple audio transformer and a few parts.=20
>>> Look for the article called=20
>>> "gimmicks old and new" I think that's where you'll find the field =
>> strength
>>> meter.
>>> =20
>>> Let me know if you can't find it and care <GRIN>
>>> 73
>>> tom Fowle WA6IVG
>>> =20
>>> On Wed, Nov 11, 2015 at 03:27:40PM -0700, Ed Malmgren wrote:
>>>> Where can a person get a field strength meter, audio of corse.  I am =
>> not in=20
>>>> the moode to build things other than antennas any more? Could it be =
>> lazy or=20
>>>> have I done too much of those kind of things hi hi.  73
>>>> =20
>>>> ED K7UC=20