MidNite Classic is FCC class B rated

[Halfcrazy]

We pasted CE and FCC class B 

[Vic]

HC,
Great News!
My CL 150 is just one year old.  Were things added to or midified in this original design to help passing Class B?  If so,  when might any of these additions/mods find their way into distribution?

Thanks,  Vic

[niel]

congrats.

vic,
that is a good point as there were some differences between the first issued classics and the newer. i doubt there is much difference though.

[Halfcrazy]

I think boB will be along to chime in. I do not think any changes where made for the purpose of emissions. we did notice that the newer boards seem to be a little different. For instance I have a Classic 16 inches form my 6 meter repeater 53.290 TX and the old Classic I had in the 30's would just break the squelch on the repeater in full sun. The new one seems to have shifted that birdie a little.

I also have a 220 repeater 16 inches from the Classic on 224.84 with a laptop running echo-link on it (KB1UAS-R if anyone is interested) with 0 change in the noise if I manually open the squelch. I can tell you I tried a few of the competitors in this environment and it was not pleasant. The XW 150vdc controller was quite though.

I also do not really see much of any difference on the HF radio and it is you guessed it 16 inches from the Classic

The system runs with 220 watts of PV and a 12 volt battery bank made up of 4 6 volt Trojan golf cart batteries.

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[boB]

HC,
Great News!
My CL 150 is just one year old.  Were things added to or midified in this original design to help passing Class B?  If so,  when might any of these additions/mods find their way into distribution?

Thanks,  Vic

The only thing that is semi-new is one little teeny capacitor added (~0.01 uF)  from negative to ground for common mode filtering.  This is on the power board.  Where the Classic was close to the limit line was around 45 to 50 MHz or so and adding that cap brought the emissions down to about 4 dB under the line at that frequency band.  The other thing we tested with were some ferrite toroids around all 4 input/output wires.  Without those ferrites, the emissions are ~just~ over the limit line around 45 to 50 MHz.  Above this it is quiet and is normally  very much under the limit line. Those ferrites were mainly for CE because FCC is even easier to pass than CE emissions.  Without any other filtering, the Classic is pretty quiet.  I should post the spectrum results because it is fairly impressive.  Even I was surprised at how good it turned out.

boB

[boB]

Here is a pic of Mario in one of the chambers with us at the testing facility with the Classic.

boB



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[Vic]

OK boB,  Thanks,

Great news.  My main interest is on the lower bands.  But,  when one gets down to it,  there is little interesting on those bands when the sun is high in the sky.

Winter Long-Path on 40 M starts about an hour before sunset (to areas of interest to me),  so,  one could just shut off the CC if it was making trouble ..  prob would not be making much power,  then anyway.   And on 40 M,  directional antennas are fairly easy to come by.

Have been using large CM type 31 toroidal filters very close to the exit/entry of the conductors to any/all CC.  Seems like good practice.

Would love to see the plot of emissions vs amplitude.

Great Job!  I need one more Classic 150 for a new Hammie Radio power system,  so this is very good news,  indeed.    73   Thanks, Vic,  K6IC

[boB]

OK boB,  Thanks,

Great news.  My main interest is on the lower bands.  But,  when one gets down to it,  there is little interesting on those bands when the sun is high in the sky.

Winter Long-Path on 40 M starts about an hour before sunset (to areas of interest to me),  so,  one could just shut off the CC if it was making trouble ..  prob would not be making much power,  then anyway.   And on 40 M,  directional antennas are fairly easy to come by.

Have been using large CM type 31 toroidal filters very close to the exit/entry of the conductors to any/all CC.  Seems like good practice.

Would love to see the plot of emissions vs amplitude.

Great Job!  I need one more Classic 150 for a new Hammie Radio power system,  so this is very good news,  indeed.    73   Thanks, Vic,  K6IC

Thanks !   I knew the emissions of the Classic were pretty good when first had one running next to my car (mobile HF) and was pretty happy then.

Remember that FCC Class B does not  measure below 30 MHz, but from what I could see, it started dropping from 40 down to 30 MHz so I assume that at lower frequencies it will drop more (to a point) I suppose  (and I hope !)  Will post a pic of the spectrum here soon.

boB

[Vic]

Not wanting to get too technical, ...   but ...

For devices that are Line-Operated,  conducted emissions tests are done for FCC B.  This test coveres 100 Khz to 30 Mhz IIRC.   Since this CC is not AC power line operated,  are there NO conducted emission tests?  And you mean that there are NO tests below 30 Mhz at all??!!?

This is the area that causes most issues for Hammie types,  and BC Engineers.

If there are no tests for conducted emissions,  then how do you handle incidental radiated emissions from the HIGH POWER leads to/from the CC?  Are these double shielded,  or something?

Direct radiated emissions through the AL casting should be well attenuated ...   Will not belabor this much more.  OR a short PM exchange would be fine,  as this is uninteresting to most,  bet, Thanks, Vic

[boB]

Yes, Vic.   Sorry to break it to the world but anything below 30 MHz is not for FCC class B testing for DC products.  I think that most people think
that below 30 MHz is part of the tests.    It can be measured though of course.  Actually, the testing lab has a loop antenna that can measure radiated emissions below 30 MHz but there would be no other charge controllers to compare against.  Having said this, I do think that the  Classic is very good below 30 MHz compared to other charge controllers.  Class B does go to 2 GHz though in our case.

The Classic and most charge controllers also normally have their wires in conduit and that also helps a bunch. That is the shielding.  Flexible conduit is the way to go.  As I know and you know, most of that low frequency radiation comes from the conducted common mode conduction from the wires and the emissions from the unit itself is usually very low.

I talked with a ham recently that lives near us, first on 20 meters when he was in Hawaii, that actually modified an MX60 to be respectable for HF operation using a couple of off the shelf filters.  It wasn't Corecom but another company about as high on the list of manufacturers.  Can't remember off hand the name right now.

I don't have a problem discussing this stuff on the forum.   Other ppl don't have to read it of course.    The more the better as far as I'm concerned.  We really need more techies in this field.

I did get a PDF of the spectrums of our test but they were just of the peaks and semi-peaks but I had a printout of a few of them.  With and without the ferrites but the one without ferrites went above the line at around 40 MHz about 6 dB.  Here is a phone-pic shot of the spectrum with the ferrites.  There is another one that is WAY down and I ~think~ it must have been one of just the aux supply running or something like that so I won't post that unless someone wants to see it.  The tests I did myself after our pre-scan a few months ago showed the emissions dropping somewhat below 30 MHz with my loop antenna but this graph doesn't look like it would do that.  I feel that this 40 MHz peak is from some resonance.  Sometime I will look closer at lower frequencies but it may not get much better than it is now without reducing switcher efficiency.

boB


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[Vic]

boB,

Very interesting.  Thanks for the education.  Have been a hardware design eng,  and as such was responisble for getting products emission compliant.  Was interesting.

Great news on Class B. ... BTW,  I spoke with some chap on 17 Meters a few years ago.  He was in the NW somewhere,  and mentioned that he was using some filters in a can,  and that they were fairly effective.  Think that they were a form of Pi filter.  The  CM chokes in use here plus all conductors being run in EMT or RGD conduit helps a lot.  Only parts of the PV array are unshielded.

OK  Thanks again,  Vic

[phonetic]

At my remote weekender location 1000 meters away from the nearest Power/EMI source..my HF set up cannot dectect any RFI from the Classic 150..the noise floor is at my queit HF location is  -120dBm,  my 80 meter terminated loop antenna is aprox 30 metres away form the  PV array & Classic 150.
Im sure  the Classic meets any CE FCC or  ACMA C-tick

Frank
VK3ZFS

[boB]

At my remote weekender location 1000 meters away from the nearest Power/EMI source..my HF set up cannot dectect any RFI from the Classic 150..the noise floor is at my queit HF location is  -120dBm,  my 80 meter terminated loop antenna is aprox 30 metres away form the  PV array & Classic 150.
Im sure  the Classic meets any CE FCC or  ACMA C-tick

Frank
VK3ZFS

Thank you for that report, Frank !   Last summer I had 4 ---   220 Watt modules out in front of the shop running a Classic inside and had my car, mobile HF rig, parked next to the array.  The EMI was fairly small but if I looked around the bands, I could hear some interference.  The antenna was a foot or two from those modules.  Driving across the parking lot, I noticed any EMI pretty much go away.  I tried adding some ferrites around all 4 input and output lines and the levels dropped even more.  I am pretty happy with how it turned out, considering my past experience with other controllers and one in particular I had designed at another company.  Months later, as we show below here (I think), we passed the CE and FCC testing.   Still, we needed the ferrites to get that 45 MHz peak down below the reference line but it was barely above the line without the ferrites. 

boB