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Old November 17th 03, 09:35 PM
Skipp
 
Posts: n/a
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I don't know why you're having so many problems. I've aligned many the VHF
Engineering and Hamtronics VHF (and UHF) Transmitters through the years
using the volt meter alignment information.

I was at Kinkos (my office anywhere) making copies of the VHF Engineering
2 meter tx strip yesterday. If you are actually serious about building
this type of transmitter, drop me a note through the
http://sonic.ucdavis.edu web server Email icons and I'll send you copies
or scans of the paperwork.

chow for now
skipp
http://sonic.ucdavis.edu

: Ashhar Farhan wrote:
: I recently brewed up a small portable NBFM tranceiver for the local
: ham group. Smallness and low cost were a requirement. My initial
: design which is working well is based on an 18MHz crystal that i
: multiply in balanced doublers three times over to 144MHz (using two
: transistors in push-pull at each stage) followed by a 500mW 2N3866 PA.
: I have found that without a high bandwidth oscilloscope (I used a tek
: 465) it is impossible to correctly align the tx. I am now considering
: switching to a scheme where i can run a VCO at 144MHz directly and
: lock it to a lower fundamental crystal. i can do this by:
: a) injection locking the VCO with the a crystal oscillator. I have
: seen almost no use of this method (EMRFD just mentions it in one line)
: in amateur literature. my last post on this topic went unanswered last
: week.
: b) using a simple first order PLL. is there a way to simplify this?
: the cost of a PLL IC or even an SBL mixer would be too high.
: c) use an overtone directly on 144MHz (9th overtone in a butler
: config) and phase modulate its output. Any pointers to a phase
: modulator operating at VHF?

: - farhan