The other method is to use a phase-locked-loop: VCO at output frequency,
divided down to the source frequency, phase compared with the source,
phase comparator output controls the VCO via a loop filter.
This is a useful way of locking one frequency to another apparently
unrelated one which I have used successfully in the past and which of
course is the basis for a synthesiser. I used a CD4046 PLL chip with a
CD 4059 programmable divider but have no idea if these are still
available as it was about 25 years ago! Phase noise might be a problem
if you are looking for absolute spectral purity.
Tom, G3OLB
In message <[email protected]>, Stewart Bryant
<[email protected]> writes
Use three push-push doublers in series.
minicircuits do one, but the LF spec is 50KHz, so you might have
to build a discrete one for the first stage (center-tapped transformer,
two-diodes and a capacitor)
Stewart G3YSX
gii3kev wrote:
Hello All
There are numerious chips available for dividing frequency but what is
available for multiplying, eg.
I have a W & G freq generator 200 hz - 20 khz and want to use it for
136 khz as a driving tx source. Is there a chip device that multiplies
this up to the desired freq.
say x 8 1600 hz - 160 khz.
I am trying to avoid the convential method with descrete components,
another approach would be to mix/hetrodyne it to the desired freq with
an appropriate xtal osc cct.
All advice appreciated.
73 de Mal/G3KEV
--
Tom Boucher
Telemetry Consultants Limited
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