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How to reduce RF power out stepwise with a ubitx V3?

Jep
 

10W RF out from the ubitx might be too much for a 50-100W power amplifier. 
How could RF out be reduced stepwise down to 1W?
Any suggestion is very welcome
Jep, IZ0WIT 

 

Turn RV1 clockwise to reduce power!

Raj

At 15/06/2020, you wrote:
10W RF out from the ubitx might be too much for a 50-100W power amplifier.
How could RF out be reduced stepwise down to 1W?
Any suggestion is very welcome
Jep, IZ0WIT

Jep
 

Yes Ray, certainly that works:
I would prefer a panel control of power out to have the possibility to run the ubitx as a low-power driver or as a standalone rtx at its full power capability without necessity to access the cabinet inside to change modality. I must argue that the only way to have this feature is to move RV1 to the front panel?
Bests, Jep

Evan Hand
 

Jep,
Others on this board have installed multiple RV1s with a switch to select between them or to flatten power across bands, to relays driven by the band selector signals.  Since the power out varies so much by the band, if you are not going to work only one band, I would suggest that you bring it out to the front panel, and through experimentation work out by band the correct setting for the mode you want to use.  That would be easier if you had a scale for the control.

The above is just a suggestion.  You can search the board or the internet for flattening ubitx power output by band.
https://ubitx.net/2018/06/28/2539/

73
Evan
AC9TU

Jep
 

Evan and Raj, 
Thank you for the limpid suggestions; then I will consider installing a pot with a long axe to avoid long wires travelling over the circuit board.
Alternatively, as I do normally use the ubitx for the 40m band only, even a simple switch and a small relay to select  hi/lo power could be an easy approach to reduce power at the level required by a Ten Tec 405 power amplifier. 
Best greetings 
Jep

 

You can Jep, just use thin coax like RG174 or similar for in and out lines and put a pot on front panel.
Some here have done it.

Raj

At 15/06/2020, you wrote:
Evan and Raj,
Thank you for the limpid suggestions; then I will consider installing a pot with a long axe to avoid long wires travelling over the circuit board.
Alternatively, as I do normally use the ubitx for the 40m band only, even a simple switch and a small relay to select hi/lo power could be an easy approach to reduce power at the level required by a Ten Tec 405 power amplifier.
Best greetings
Jep

Jep
 

Thank you Raj, that is a good idea: it would be a quick and easy way to solve my problem. Great. 
Cheers
Jep