AR8600-MK2 AOR AR8600 MK2 - useless noisy switch mode power supply

[g8tzl2004]

The 'wall wort" power supply for an AR8600 MK2 is an SRP1201500P 12v 1500mA type. I think this is also used with the AR-DV1.

This power supply results in QRM / noise across the HF band...not only with the AR8600 BUT also with other HF receivers plugged into adjacent sockets!!

Why does AOR supply noisy switch mode power supplies with its radios?

How hard is it to build a switch mode power supply which is quiet? How is saving a few $ on missing out RFI suppressions caps etc in the power supply going to help AOR?

Switch mode power supplies can be built so that they are RF quiet...although I guess it may be better to use a traditional linear power supply.

I have previously checked out a number of switch mode power supplies with my Yaesu FT817. I found a small 12v 3A "laptop type" which I got at a junk sale for $1 (and used with Christmas lights...go figure) is RF quiet across the HF bands..so it can be done My Samlex and Astron switch mode power supplies are also RF quiet...although the Samlex is a Euro version which has additional RFI suppression caps installed to meet EU regulations...I'm not sure whether the North American version is still missing the caps...but they should be installed as standard

I also have a small REGULATED linear "wall wort" 12v 800mA power supply which should be OK as the AR8600 current consumption according to the specs is a nominal 350mAh. BEWARE that most small LINEAR (ie NOT noisy switch mode) "wall wort" type power supplies are NOT regulated...so if the voltage is measured with no load it will NOT be 12v but something like 16-18v!!

What does anybody else use with an AR8600? Is there an original AOR power supply which is RF quiet?

 

[AOR-262]

@g8tzl2004

I 'think' receiver manufactures supply their products with switching PSU's because they are cheap to make and keep the overall cost down and supplying a PSU quickly gets you going. The experienced users know the ridiculous RF noise generated by these switching PSU's and know better to use them including using switching PSU's near receiving equipment such as Laptop PSU's etc. Some might argue different but my 2-cents would be to steer well clear from using switching power supplies.

The AOR 8600 Mk2 I believe is no longer in production; I read somewhere AOR had stopped making it - as their focus now is on their best seller the DV-1. When I bought my Mk2 and it was supplied with the original PSU (AOR Part No. #952500) which outputted 15V, 800mAh Regulated. I'm not sure if that PSU is switching BUT outputs a regulated DC supply. I never had any issues with that PSU until I bought the Icom IC-R8600. The issue I had wasn't with the AOR PSU but with the supplied Icom AD-55NS PSU (which was a switching PSU). That generated a lot of RF interference that played havoc with my AOR below 30 MHz using AM Mode and some frequencies using USB Mode.

So, I bought the Nevada PS-08 Regulated Linear PSU. That powers both my R8600 and my AOR 8600 Mk2 and the AOR LA400 Active Antenna.

Perfect link below ...

Nevada PS-08 6-8A Regulated Linear Power Supply

First Light Optics - Suppliers of Astronomy telescopes, binoculars and accessories from Skywatcher, Celestron, Meade, William Optics, Atik, Imaging Source, Starlight Xpress, ADM, Moonlite, Catseye, Hutech and others.

www.firstlightoptics.com

 

[g8tzl2004]

My AR8600 MK2 is a late production radio and was supplied to me (as a used radio) with an SRP1201500P...but maybe it was originally supplied with an AOR Part No. #952500 power supply...but the SRP1201500P is now used with the AR-DV1.

OK on the noisy Icom IC-R8600 switch mode power supply. I also received a noisy switch mode power supply with my Icom IC-R1500...so Icom are as guilty as AOR for supplying noisy power supplies

BUT how much does it cost to build a switch mode power supply with proper RFI suppression?? It must just be a few cents You would think that both AOR and Icom would insist on using an RF quiet switch mode power supply....and they can be manufactured!!

OK on the Nevada PSU...I have been using the AOR "cigar" plug with my main 30A linear power supply...but it would be nice to just use a small dedicated RF quiet power supply rather than having to rely on a power supply which is a big as the AR8600

By the way, its confusing that Icom called their radio an R8600 vs AOR's AR8600 ....although the Icom R8600 HF performance is in a different league compared to the AOR AR8600 with HF reception reported to be as good as an Icom IC-7300

How does your Icom IC-R8600 compare with the AOR AR8600 MK2 for RX sensitivity on VHF and UHF in a side by side comparison?

 

[AOR-262]

@g8tzl2004

Here's a video I made uploaded to my YouTube Channel ...

 

[g8tzl2004]

Have you tried listening to a very very weak hard to understand signal on air band (distant ATIS?), VHF (distant 2m repeater?) and UHF (distant 70cms repeater?) and using the same identical antenna switch from one radio to another and see which radio provides the best reception.

 

[AOR-262]

@g8tzl2004

I haven't tried what you mentioned, no. My setup is not professional in any way. I'm just playing with both receivers to compare the both for the setup I have here i.e. the antenna, the location, signals I am able to receive from my home QTH ... and I filmed the both receivers. If truth be known, this really isn't a true comparison of the AOR 8600 Mk2 v Icom IC-R8600 especially for someone deciding whether to buy the AOR or the Icom. My preference of these receivers when performing a memory scan of stored frequencies is the AOR. It was just unfortunate on the day I had them both running that the AOR quite a few times stopped on weaker civil airband VHF frequencies while the Icom flew past when it should of stopped.

 

[MDScanFan]

I recall watching that video a couple times last year when I was debating a R8600 purchase. I appreciated the test and upload. As you point out this may not be a true comparison of the two receivers. Identical antennas, similar speakers (either both internal or external on the same speaker), and optimized settings are desired for a fair comparison. If the description is correct, then the radios were using different antennas, which automatically makes for a skewed comparison. Also, the AOR was using an external speaker and sounded much better. It is not clear what settings were used on the R8600 for this test. I find weak civil air reception works best at my location with its preamp enabled and the bandwidth narrowed up a bit vs the default setting.

@g8tzl2004

Here's a video I made uploaded to my YouTube Channel ...

 

[g8tzl2004]

It would be interesting to check the RX sensitivity between the AOR AR8600 and Icom R8600.

On the AOR set the SQ to minimum (or open the SQ for white noise) and use the SFM narrow FM filter (which gives best narrow FM RX sensitivity). Then find a really really weak (ie in the noise) but always busy VHF voice FM signal. Then switch the same antenna to the Icom R8600 tuned to the same frequency with the SQ at threshold (or open) and the most narrow FM filter used and see if the weak signal sounds weaker or stronger

My Icom R20 is NOT as sensitive as my AOR 8200 mk3 on Low band (66 -88 MHz), VHF or UHF...but is more sensitive on 23cms (1297 MHz).

 

[cherubim]

What does anybody else use with an AR8600? Is there an original AOR power supply which is RF quiet?

I use a a genuine AOR power supply (AOR Part No: AA8600EC). It's 12V 800mA. It's a small and heavy linear power supply.

It's pretty quiet, even on LF and HF.

I suspect AOR included cheap switch mode power supplies at a later stage to cut costs.

 

[g8tzl2004]

OK on the AOR linear 12v 800mA power supply...its a pity my AR8600 MK2 did not come with that nice quiet version!!

800mA is OK for the AR8600 which according to the service manual requires only 400mA..but I don't think its enough current for the AR-DV1 so the switch mode SRP1201500P 1500mA type is supplied...but it could be built with better RFI filtering to get rid of the QRM!!

I think that a linear 800mA power supply must only cost $5-$10 to manufacture...and it would save AOR having to suffer negative comments about noisy useless switch mode power supplies!!