Pete, am looking for a good variable attenuator for UHF
 

I am building a transmitter combiner for non-conforming wideband FM
signals and need an high-level AGC stage that can control over a 40 dB
range and can handle up to 5 Watts input. I have a real clean final
amp
http://www.empowerrf.com/docs/1043.doc
but it insists on having a 0 dBm input for full power and minimum
products. Thanks.

Pete, am looking for a good variable attenuator for UHF
 

On Thu, 30 Nov 2006 14:26:25 GMT, David wrote:

I am building a transmitter combiner for non-conforming wideband FM
signals and need an high-level AGC stage that can control over a 40 dB
range and can handle up to 5 Watts input. I have a real clean final
amp
http://www.empowerrf.com/docs/1043.doc
but it insists on having a 0 dBm input for full power and minimum
products. Thanks.

I'm leaning toward 2 quad pin diode attenuators in series.

Pete, am looking for a good variable attenuator for UHF
 

In article ,
David wrote:

On Thu, 30 Nov 2006 14:26:25 GMT, David wrote:

I am building a transmitter combiner for non-conforming wideband FM
signals and need an high-level AGC stage that can control over a 40
dB range and can handle up to 5 Watts input. I have a real clean
final amp http://www.empowerrf.com/docs/1043.doc
but it insists on having a 0 dBm input for full power and minimum
products. Thanks.

I'm leaning toward 2 quad pin diode attenuators in series.

You may want to re-consider that since pin diode attenuators have large
intermodulation products.

Then again you did say it is a non-conforming transmitter.

If you care about intermodulation then go with an electromechanical
type attenuator.

--
Telamon
Ventura, California

Pete, am looking for a good variable attenuator for UHF
 

On Sat, 02 Dec 2006 02:55:04 GMT, Telamon
wrote:

In article ,
David wrote:

On Thu, 30 Nov 2006 14:26:25 GMT, David wrote:

I am building a transmitter combiner for non-conforming wideband FM
signals and need an high-level AGC stage that can control over a 40
dB range and can handle up to 5 Watts input. I have a real clean
final amp http://www.empowerrf.com/docs/1043.doc
but it insists on having a 0 dBm input for full power and minimum
products. Thanks.

I'm leaning toward 2 quad pin diode attenuators in series.

You may want to re-consider that since pin diode attenuators have large
intermodulation products.

Then again you did say it is a non-conforming transmitter.

If you care about intermodulation then go with an electromechanical
type attenuator.

This is for UHF. ''Non-conforming'' is meaning the carriers are not
synched and don't add up cleanly to the sum of their individual
milliWatts. This creates heat in the combiner which can also increase
3rd order products. I'm using this:

http://www.minicircuits.com/pdfs/ZB5CS-920-10W.pdf

As I understand it, pin diode attenuators are pretty clean within a
certain attenuation range. I'd use off the shelf except nobody I can
find makes one that can handle +37 dBm.

This circuit will be used for AGC so we're pretty much locked into an
electronic solution. Thanks.

Pete, am looking for a good variable attenuator for UHF
 

In article ,
David wrote:

On Sat, 02 Dec 2006 02:55:04 GMT, Telamon
wrote:

In article ,
David wrote:

On Thu, 30 Nov 2006 14:26:25 GMT, David wrote:

I am building a transmitter combiner for non-conforming wideband FM
signals and need an high-level AGC stage that can control over a 40
dB range and can handle up to 5 Watts input. I have a real clean
final amp http://www.empowerrf.com/docs/1043.doc
but it insists on having a 0 dBm input for full power and minimum
products. Thanks.

I'm leaning toward 2 quad pin diode attenuators in series.

You may want to re-consider that since pin diode attenuators have large
intermodulation products.

Then again you did say it is a non-conforming transmitter.

If you care about intermodulation then go with an electromechanical
type attenuator.

This is for UHF. ''Non-conforming'' is meaning the carriers are not
synched and don't add up cleanly to the sum of their individual
milliWatts. This creates heat in the combiner which can also increase
3rd order products. I'm using this:

http://www.minicircuits.com/pdfs/ZB5CS-920-10W.pdf

As I understand it, pin diode attenuators are pretty clean within a
certain attenuation range. I'd use off the shelf except nobody I can
find makes one that can handle +37 dBm.

This circuit will be used for AGC so we're pretty much locked into an
electronic solution. Thanks.

You might be interested in reading this
http://www.weinschel.com/pdfiles/wd&dartice4-99.pdf

This vendors makes all types of attenuators.

--
Telamon
Ventura, California

Pete, am looking for a good variable attenuator for UHF
 

Telamon wrote:


You might be interested in reading this
http://www.weinschel.com/pdfiles/wd&dartice4-99.pdf

This vendors makes all types of attenuators.

--
Telamon
Ventura, California

Thanks for the link.
While I don't work in transmitter land, this will ruin their day
Monday. They have several PIN attenuators in the ATSC
combiner path and we have some IMD issues.

Terry

Pete, am looking for a good variable attenuator for UHF
 

In article . com,
wrote:

Telamon wrote:


You might be interested in reading this
http://www.weinschel.com/pdfiles/wd&dartice4-99.pdf

This vendors makes all types of attenuators.


Thanks for the link. While I don't work in transmitter land, this
will ruin their day Monday. They have several PIN attenuators in the
ATSC combiner path and we have some IMD issues.

There are more applications notes on that page to check out if you have
those kinds of problems.

--
Telamon
Ventura, California

Pete, am looking for a good variable attenuator for UHF
 

On Sat, 02 Dec 2006 18:09:36 GMT, Telamon
wrote:



You might be interested in reading this
http://www.weinschel.com/pdfiles/wd&dartice4-99.pdf

This vendors makes all types of attenuators.

Thanks. I'll contact them from the shop, tomorrow. My FOIs are
between 0.512 0.806 gHz.