[RFI] Travel trailer converter RFI solutions

[nm8rmedic]

K1TTT,Good point about the ripple. I have a battery powered scope and will check. ScottSent from my Verizon, Samsung Galaxy smartphone
-------- Original message --------From: k1ttt.dave at gmail.com Date: 7/22/22  14:42  (GMT-05:00) To: 'nm8rmedic' <nm8rmedic at rocketmail.com>, "'rfi at contesting com'" <rfi at contesting.com> Subject: RE: [RFI] Travel trailer converter RFI solutions I would be very suspicious of the growl caused by ferrites on the dc line, the only reason for that would be ripple, aka noise, on the dc output.  May be worth putting a scope on that or at least adding some serious filter caps to see if it helps.  Also double check anything that comes off the dc lines, if there are led bulbs, computers or phone chargers or supplies, a tv, etc it could be a switching supply in them that goes off when you power the dc converter off.David Robbins K1TTTe-mail: mailto:k1ttt at arrl.netweb: http://wiki.k1ttt.netAR-Cluster node: telnet://k1ttt.net:7373-----Original Message-----From: RFI <rfi-bounces+k1ttt=arrl.net at contesting.com> On Behalf Of nm8rmedic via RFISent: Friday, July 22, 2022 14:11To: rfi at contesting com <rfi at contesting.com>Subject: [RFI] Travel trailer converter RFI solutionsHas anyone on the forum succeeded in quieting the RFI from the AC to DC converter in their travel trailer?Or has anyone identified a suitable linear power supply with battery charging circuitry?Our trailer has a switching power converter rated at 55 amps. It produces RFI about every 30 khz, mainly in the 40 and 20 meter amateur bands. Powering down the converter kills them, so they are coming from the switching power supply that forms the basis of the converter.   Neither an Isobar filtering power strip, nor Mix 31 ferrite cores on the AC power cable had effect. The same cores on the DC line cause some odd ferromagnetic resonance inside the converter because it audibly growls when they are in place. Bypass capacitors on the DC line had no effect.I'm interested in hearing anyone's success story.ScottSent from my Verizon, Samsung Galaxy smartphone _______________________________________________RFI mailing listRFI at contesting.comhttp://lists.contesting.com/mailman/listinfo/rfi