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Rosie RFI Test Ham Radio

Started by onanparts, September 17, 2021, 03:04:50 PM

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onanparts

Was up at MS earlier this week, Tuesday and again on Thursday. So, I was curious how much if any RFI Rosie was emitting. Andy was doing some extended load testing of Rosie, several hours with about a 6kW load, BIG light bulbs! I parked as close to the engineering building as possible, where I could actually see Rosie through a side door window and the big lights too!

Maybe 100'-150' line of sight to her. NOTHING on the HF bands. Zip, Zilch, Naddah...:) My Icom 706 Mark IIG is not the most sensitive transceiver, but good enough for a basic, can I hear any noise at close range test. The MS factories are in an area that is very quiet, no hash n trash that's in all our local neighborhoods. Dense population...:(

I brought a portable cheap Rat Shack SW receiver with me Thursday, but Rosie was snoozing. boB and I did some interesting RFI testing on the B17 both days with the RS portable and my Icom. I'll post about that in the B17 forum later. Good news on that front too concerning RFI. :)

Sorry, no pics..Going up weekly from now on, pics , more reports to come! Stay tuned!
I got the deluxe kit, it had a solar cell and a meter.

Midnite B17-10. 50kW Cont. 150kW Surge... Me/Myself/And/I

Vic

Hi o..p,

Out of curiosity,  what type/length of aerial was connected to the 706,  for this test?

73,  Thanks,  Vic
Off Grid - Sys 1: 2ea SW+ 5548, Surrette 4KS25 1280 AH, 5.25 KW PV, Classic 150,WB, Beta Barcelona, Beta KID
Sys 2: SW+ 5548s, 4KS25s, 5.88 KW PV, 2 ea. Classic 150, WB, HB CC-needs remote Monitoring/Control, site=remote.
 MN Bkrs/Bxs/Combiners. Thanks MN for Great Products/Svc/Support&This Forum!!

boB

Quote from: Vic on September 17, 2021, 05:02:05 PM
Hi o..p,

Out of curiosity,  what type/length of aerial was connected to the 706,  for this test?

73,  Thanks,  Vic


TJ has a nice Diamond trunk mount 20m antenna.

On 20 meters, the B17 would give a VERY low level birdie at 30kHz spacing right at the big door (open) at building 10 with the B17 inside running...  About a 10 or 15 second walk inside.   These were at around 14260, 14290 and 14230 kHz. When he drove inside the building so that it was line of sight with the B17 maybe 50 feet away, the background noise at only that carrier birdie frequency went up bout 1 S unit which the background noise was sitting at around 5 above 0 so went up to maybe 6 from there.   I determined from WHEN the birdie came up to be from the DC to DC converter inside and nothing any higher level when the inverter and light bulb loads came on.   When two (2) modules came on with a large-ish AC load, I could hear a slight beating which would be because their switching frequencies are crystal controller but not phase locked of course on the 30 kHz part.

On the broad-band short wave radio on Thursday, it is somewhat worse at lower frequencies but we could still hear AM broadcast stations that were very weak to begin with.

I am pretty happy with these first tests but would still like it a bit better.   I only tried a couple of capacitors on the DC side and they did not help but there is already common mode filtering of the battery line.  This B17 also has its top open etc so not ideal.

I think it might just be not too bad !   Real testing is still necessary.


K7IQ 🌛  He/She/Me

Vic

Hi boB,  thanks for the added detail.

It is great that you and op are doing some initial testing (maybe you have already some bench tests).

Back in 2017 (IIRC) at the SPI show,  stopped by the MidNite booth for an extended visit.   Peering into the B17 chassis,  complimented Andy and Mario for you guys putting a toroid or more inside,  at that fairly early date.

Name brand inverters are usually fairly quiet,  compared to CCs,  as there are Line Conducted emission tests/compliance from 100 kHz (or,  is it 150 kHz?),  and up,  to 30 mHz,  which is a huge benefit to we HF operators,  and AM BC-band broadcasters (if there any of those still around !!?).  Verses CCs which have formal compliance tests for Radiated emissions,  which begin at 30 mHz,  as you well know  ...

73.  Thanks for the info,  you folks are sure making great progress,  on many fronts.  Congrats!   GL,  Vic
Off Grid - Sys 1: 2ea SW+ 5548, Surrette 4KS25 1280 AH, 5.25 KW PV, Classic 150,WB, Beta Barcelona, Beta KID
Sys 2: SW+ 5548s, 4KS25s, 5.88 KW PV, 2 ea. Classic 150, WB, HB CC-needs remote Monitoring/Control, site=remote.
 MN Bkrs/Bxs/Combiners. Thanks MN for Great Products/Svc/Support&This Forum!!

onanparts

I'll add the HB and Barcelona to my basic RFI tests next week! boB said they have a spectrum analyzer around they planned to dust off for some real testing. :)
I got the deluxe kit, it had a solar cell and a meter.

Midnite B17-10. 50kW Cont. 150kW Surge... Me/Myself/And/I

boB

Quote from: Vic on September 17, 2021, 07:53:58 PM


Back in 2017 (IIRC) at the SPI show,  stopped by the MidNite booth for an extended visit.   Peering into the B17 chassis,  complimented Andy and Mario for you guys putting a toroid or more inside,  at that fairly early date.



I missed seeing you in 2017 ?!?!?!?!   I thought I was at that SPI ?

Maybe I wasn't ???

So, CC's are normally non-isolated and so maybe that is why they have more common mode noise ?

Guessing there but might be ?

boB
K7IQ 🌛  He/She/Me