Hi, is it possible to get a realtime attenuated signal (55-60 dB) from the output of OM-Power or others amplifiers that don't have the output connector carrying this signal?
Any market product available?
Many thanks.
Predistortion on OM-Power amplifiers?
Re: Predistortion on OM-Power amplifiers?
There are any number of market products available, none of which interested me so I built my own 18K-ohm pure resistive sampler that connects directly to the SO-239 jack on the back of my amp.
Disregard the jumble of ancillary resistors and variable pots in the picture, that box was a prototype. The final circuit consists of the six 2-watt Allen Bradley 12K-ohm carbon composition resistors in a series/parallel arrangement that provide 18K-ohm of measured resistance. That arrangement allows PureSignal to function correctly at any power level from a barefoot 25 watts to full legal maximum power.
Mark
Disregard the jumble of ancillary resistors and variable pots in the picture, that box was a prototype. The final circuit consists of the six 2-watt Allen Bradley 12K-ohm carbon composition resistors in a series/parallel arrangement that provide 18K-ohm of measured resistance. That arrangement allows PureSignal to function correctly at any power level from a barefoot 25 watts to full legal maximum power.
Mark
Re: Predistortion on OM-Power amplifiers?
I like the Xtronic units, but HRO never seems to be in stock:
https://www.hamradio.com/detail.cfm?pid=H0-015644
Apparently you are not aware that OM makes their own coupler
https://www.arraysolutions.com/index.ph ... t_id=14897
For new amp's OM offers this option:
https://www.arraysolutions.com/index.ph ... t_id=14891
https://www.hamradio.com/detail.cfm?pid=H0-015644
Apparently you are not aware that OM makes their own coupler

https://www.arraysolutions.com/index.ph ... t_id=14897
For new amp's OM offers this option:
https://www.arraysolutions.com/index.ph ... t_id=14891
Re: Predistortion on OM-Power amplifiers?
I can personally recommend this one made by a couple of retired Tektronix engineers. It's sort of expensive but built like it came from Tektronix. And for an extra $75 it will come with its own NIST certificate 
https://preciserf.com/shop/ddc545-dual- ... l-coupler/
73,
Bryan W4WMT

https://preciserf.com/shop/ddc545-dual- ... l-coupler/
73,
Bryan W4WMT
Re: Predistortion on OM-Power amplifiers?
PureSignal doesn't need a directional coupler, so the extra money expended on one of those is wasted on PS.
Mark
Mark
Re: Predistortion on OM-Power amplifiers?
It doesn't need it to function, but can puresignal make more accurate corrections if only forward power is being sampled?K1LSB wrote:PureSignal doesn't need a directional coupler, so the extra money expended on one of those is wasted on PS.
Mark
Re: Predistortion on OM-Power amplifiers?
Forward power should be the only thing that's being sampled and fed back to PS.AG5CK wrote:It doesn't need it to function, but can puresignal make more accurate corrections if only forward power is being sampled?K1LSB wrote:PureSignal doesn't need a directional coupler, so the extra money expended on one of those is wasted on PS.
Mark
So, on reflection (pun intended) I guess your point is valid!

Mark
Re: Predistortion on OM-Power amplifiers?
Many thanks for any suggestion.
Best 73s.

Best 73s.