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eHam Forums => Station Building => Topic started by: N9FB on April 18, 2009, 05:50:05 PM



Title: power supply proximity question
Post by: N9FB on April 18, 2009, 05:50:05 PM
Is there a prefered practice in terms of power supply placement and if so what is it?  farthest away from the oscillator side of the xcvr, or is anywhere just fine?  uis stacking a rig on top of a xcvr okay?  why or why not?  

i am now the proud owner of a Ten-Tec Scout, an Astron SL-10A power supply (same as Ten-tec 937 i believe), and a multiband inverted vee up 35 ft. No plans right now to use the rig as anything but my base station.  

thanks in advance for your input -- i learned the theory when i was 15, and took a loooong absence from the airways between 1977 and today.



Title: power supply proximity question
Post by: W3LK on April 18, 2009, 07:18:41 PM
When I'm running a station away from home, the portable rig (DX-70TH) sits right on top of the Samlex switching PS.

At home my Astron sits about two feet from the TS-570.

I have not found it to make any difference where the PS sits in relationship to the rig.

73,

Lon - W3LK
Naugatuck, Connecticut


Title: power supply proximity question
Post by: WB2WIK on April 18, 2009, 08:41:56 PM
It usually doesn't make any difference; however with linear (not switch mode) power supplies, the big field generated by the power transformer can sometimes couple into sensitive audio circuits and create a hum.  If that happens, move the power supply!

With SMPS (switching supplies), this shouldn't  happen at all.

Because my "main station" power supply is an Astron RS-70M (70A, it feeds everything), I keep it on a low shelf down about ankle level, not to separate it from the gear but only because it's freaking heavy.

WB2WIK/6


Title: power supply proximity question
Post by: KB9CRY on April 19, 2009, 06:07:07 AM
On the floor under the table.  Also, it's always on.


Title: power supply proximity question
Post by: N9FB on April 19, 2009, 07:09:04 AM
sorry, i should have written SL-11A supply not SL-10A...


Title: power supply proximity question
Post by: AA4PB on April 19, 2009, 05:02:41 PM
Ordinarily proximity is not an issue, regardless of the power supply type. I've seen one radio that had 60Hz FM in the signal when it was setting directly on top of the power supply. Moving the supply next to the radio took care of it. I've seen one issue where a friend mounted a 2M mag mount on top of an inexpensive power supply and the RF put the supply in over-voltage which blew the finals in the transmitter.

Normally, the supply on the table next to the radio is fine - leave a little room for air circulation and cooling.