I've heard that high side mixing is preferred to low side
mixing because the LO harmonics will be higher and less
likely to cause problems.

It also seems to me that (f1 + f2) is typically discarded
and what's used is just the (f1 - f2).

Any truth to either of these impressions? If so, what's
the rational?

Depending on the availability of off the shelf VCO parts
one might what to use (f1 + f2) or low side mixing and I
was just curious what (if any) additional problems I should
look out for.

-- John

wrote:
I've heard that high side mixing is preferred to low side
mixing because the LO harmonics will be higher and less
likely to cause problems.

It also seems to me that (f1 + f2) is typically discarded
and what's used is just the (f1 - f2).

Any truth to either of these impressions? If so, what's
the rational?

Depending on the availability of off the shelf VCO parts
one might what to use (f1 + f2) or low side mixing and I
was just curious what (if any) additional problems I should
look out for.

-- John


It's easier to dodge harmonics and higher-order mixing products.

For _any_ IF/LO combination you should make a table of the possible
mixing products of the first few harmonics of your RF range with
_several_ harmonics of your LO range (most modern mixers generate _lots_
of odd harmonics of the LO internally). If any of these products other
than the intended pair span the IF then you'll have problems with
spurious mixing.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

On 2007-07-03, Tim Wescott wrote:

For _any_ IF/LO combination you should make a table of the possible
mixing products of the first few harmonics of your RF range with
_several_ harmonics of your LO range (most modern mixers generate _lots_

The guy who wrote rfsim99 also wrote "spur search" which will make this
table for you (same download, assuming you can find it!).

--
Ben Jackson AD7GD

http://www.ben.com/

Can anyone help on a manual or schematic for a Kepco SM36-15M
supply? Kepco wants $ 100 for a manual... ouch! Google doesn't want
to be helpful in this search.

73, Mike W5CHR
Memphis

On Sun, 8 Jul 2007 17:58:08 -0500, "Mike Lucas"
wrote:

Can anyone help on a manual or schematic for a Kepco SM36-15M
supply? Kepco wants $ 100 for a manual... ouch! Google doesn't want
to be helpful in this search.

73, Mike W5CHR
Memphis


Don't know if it'll help, but here are 2 Kepco power supply schematics
we have he

http://www.talonix.com/images/kepco1.pdf

http://www.talonix.com/images/kepco2.pdf

Brian

"Brian" wrote in message
...
On Sun, 8 Jul 2007 17:58:08 -0500, "Mike Lucas"
wrote:

Can anyone help on a manual or schematic for a Kepco SM36-15M
supply? Kepco wants $ 100 for a manual... ouch! Google doesn't want
to be helpful in this search.

73, Mike W5CHR
Memphis


Don't know if it'll help, but here are 2 Kepco power supply schematics
we have he

http://www.talonix.com/images/kepco1.pdf

http://www.talonix.com/images/kepco2.pdf

Brian

Brian-Thanks for the links... the first one was close enough to what I
have to answer my questions. This thing followed me home from a hamfest,
maybe for use as a HV supply for an FET amp. Again, thanks for the post.

73,Mike W5CHR
Memphis