I have a couple of Astro Little Devil 11 meter amps that came out of
an estate.

Wondering of anyone ever succesfully converted one of these to 6
meters?

I'm using a Ten Tec 6 meter Transverter on my Kenwood TS-450S and
could use a little more "UMPH".

I could use a schematic showing which trim caps are input and which
are output if anyone might have one.

Terry

WB0VQP

wrote in message
...
I have a couple of Astro Little Devil 11 meter amps that came out of
an estate.

Wondering of anyone ever succesfully converted one of these to 6
meters?

I'm using a Ten Tec 6 meter Transverter on my Kenwood TS-450S and
could use a little more "UMPH".

I could use a schematic showing which trim caps are input and which
are output if anyone might have one.


Terry -

10 meters is 28 to 30 MHz and 6 meters is 50 to 54 MHz.

IF this is the Astro that uses the sweep tubes that are now $ 40 to $ 50
each ... Don't bother.
That is a money pit solution ... and sweep tubes if they do operate at 50
MHz have low output.
Most 11 meter amps were built fast and cheap for a quick buck.
At best - it may be a candidate for parts.

You have probably heard that there are suitable CB amp candidates for six
meter conversion;
the problem is, this will be very model-specific and NO general statement
really applies.

If the original design was truly linear (not just by virtue of a label, but
by virtue of correct electronic bias
and stabilization circuitry) and used devices rated for operation ABOVE 50
MHz,
chances are it can be converted by changing the input and output tuned
networks,
and possibly the RF decoupling circuitry (DC power to devices).

For solid state amplifiers that I see everywhere now that the sunspot cycle
is again down,
when suitable 50+ MHz transistors are used, simply looking those devices up
in their manufacturer's
data book (or application notes such as Motorola's) will reveal an actual,
tested and proven
50 MHz amplifier circuit which would be easy to copy.

IF the only circuit published by the device manufacturer is for an amplifier
operating below 30 MHz,
that's a pretty good sign the devices won't provide any gain at 50 MHz...

BTW, a good 6 meter yagi (which is very easy to build and much smaller than
10 meter beams)
will yield more dB increase for less dollars than the amplifier.

Greg
w9gb

Greg,

IF the only circuit published by the device manufacturer is for an amplifier
operating below 30 MHz,
that's a pretty good sign the devices won't provide any gain at 50 MHz...

BTW, a good 6 meter yagi (which is very easy to build and much smaller than
10 meter beams)
will yield more dB increase for less dollars than the amplifier.
Not totally true.

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm

I totally agree with you on the antenna.

(((73)))
--
Philip de Cadenet G4ZOW
Transmitters 'R' Us
http://www.transmittersrus.com

"Philip de Cadenet" wrote in message
...
Greg,

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm


That's odd, since the SD1450 specifications were for the commercial FM
broadcast industry (88 - 108 MHz),
and is rated at 150 watts for 18 watts drive. Price is virtually the
ame - maybe its higher for you in UK

Greg
w9gb

Greg,

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm


That's odd, since the SD1450 specifications were for the commercial FM
broadcast industry (88 - 108 MHz),
and is rated at 150 watts for 18 watts drive. Price is virtually the
ame - maybe its higher for you in UK
Where did you get the SD1450 from!

Check out our device he

http://www.angliac.com/st/data_from_st/2846.pdf

Give it a minute to load as it's a PDF page.

(((73)))
--
Philip de Cadenet G4ZOW
Transmitters 'R' Us
http://www.transmittersrus.com

"Philip de Cadenet" wrote in message
...
Greg,

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our
FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm
Check out our device he

http://www.angliac.com/st/data_from_st/2846.pdf

Give it a minute to load as it's a PDF page.


So you drop from 20 Gp (db) at 30 MHz to 8 Gp (db) at 100 MHz
Would not have been my choice.

BTW, is your equipment FCC type accepted for USA usage on the commercial FM
frequencies (as required)

GB

"Philip de Cadenet" wrote in message
...
Greg,

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our
FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm
Check out our device he

http://www.angliac.com/st/data_from_st/2846.pdf

Give it a minute to load as it's a PDF page.


So you drop from 20 Gp (db) at 30 MHz to 8 Gp (db) at 100 MHz
Would not have been my choice.

BTW, is your equipment FCC type accepted for USA usage on the commercial FM
frequencies (as required)

GB

Greg,

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm


That's odd, since the SD1450 specifications were for the commercial FM
broadcast industry (88 - 108 MHz),
and is rated at 150 watts for 18 watts drive. Price is virtually the
ame - maybe its higher for you in UK
Where did you get the SD1450 from!

Check out our device he

http://www.angliac.com/st/data_from_st/2846.pdf

Give it a minute to load as it's a PDF page.

(((73)))
--
Philip de Cadenet G4ZOW
Transmitters 'R' Us
http://www.transmittersrus.com

"Philip de Cadenet" wrote in message
...
Greg,

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm


That's odd, since the SD1450 specifications were for the commercial FM
broadcast industry (88 - 108 MHz),
and is rated at 150 watts for 18 watts drive. Price is virtually the
ame - maybe its higher for you in UK

Greg
w9gb

Greg,

IF the only circuit published by the device manufacturer is for an amplifier
operating below 30 MHz,
that's a pretty good sign the devices won't provide any gain at 50 MHz...

BTW, a good 6 meter yagi (which is very easy to build and much smaller than
10 meter beams)
will yield more dB increase for less dollars than the amplifier.
Not totally true.

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm

I totally agree with you on the antenna.

(((73)))
--
Philip de Cadenet G4ZOW
Transmitters 'R' Us
http://www.transmittersrus.com