1) is my power supply
2) is the Solar DC pool pump
I can not beleive how much noise you see with the FLEX 6500, always over looked all this noise with the ICOM and KENWOOD I owned.. anyway
First, power supply is getting replaced (already increased cable size and shortened them up).
So I am looking at some honest opinions on this supply for the shack.
Astron VS Series Linear Power Supplies VS-50M
Second question, what power supply do you use?
Lastly, Have you ever measured the noise and ripple from your power supply? (if you have the equipment to do so)
Thanks for the replies
(yes I have read many posts here about power supplies, it's why I've changed several things already)
Switching power supplies are oscillators with smaller filter capacitors because less capacitance is needed to filter a higher frequency. The switching power supply inherently has more harmonics because the waveform is not purely sinusoidal. They are more prone to creating higher frequency noise. However, I have used some that are very quiet. That being said, for noise, you can't beat a well-regulated linear supply. It operates at 60 Hz. and there is very little noise, if any, generated from them. The down side is they are much heavier and consume more physical space. For noise, you can go wrong with a big well-regulated linear supply.
I have no personal experience with the Astron switching supplies, but I have heard some reports of RF hash & birdies from them.
I have 3 of the Alinco DM-330MVT supplies, one of which has been in service for over 10 years. Also, our club purchased 3 of them for use in our club station several years ago. I have found them to be extremely reliable and have NEVER experienced any RF hash or birdies from any of the 6 that I have personal experience with.
They are a little pricier than the Astron ($155 vs $130), but well worth it in my opinion.
73, Ray, K9DUR
I use an Astron RS-35 linear supply. Works fine. Took the time to open the cabinet and clean all metal-to-metal contact points. Almost all are painted, which messes with the shielding. Anything to improve the "tightness" of any enclosure is a good thing, in my book. PC cabinet likewise. Wattmeters, amplifier, too.
Check your coax (including jumpers) too. A bad connector or low-percentage braid cable can let a lot of junk into the system (and out).
Brute force line filtering on pool pumps can help. I also sunk a ground rod next to mine and connected the housing to it.
One thing I learned from Howard (KY6LA) is to use a battery to run the rig. Use the PWRGate (West Mountain Radio between it and the power supply.
Every little bit helps! It's amazing the amount of RF crud that's out there. Being able to visualize it with the Flex panadapter makes it easier to mitigate. The lower noise REALLY pays off on receive.
Seems like the Astron RS-35A might be a better choice?
BTW... i have 2 Jandy variable speed 2HP pool pumps - The motors are shielded by the manufacturer BUT I also had to make sure that everything in my pool control system (Pumps, Heaters, Controls, etc) was BONDED together to Ground and all paint was removed .
in the screw holes to make sure that there was good ground contacts in the case. Also a good idea to use corrosion protectant like NOALOX at the screws.
Similar problem in my previous home, 1HP pond pump with VFD. The VFD is just a double switching power supply feeding crud on both input and output wires. In my case 4 PS as the output was 3 phase. This pump VFD was on a circuit that also fed the outdoor lights. (a 160M endfed antenna)
Solution: (-60db but still noticeable on 80/160 and no longer wiped out the LF aircraft landing beacon on the overhead glide slope into the town airport)
- Mounted the VFD inside a Hammond shielded box (door appropriately grounded to case)
- Shielded 4 wire power cord from Hammond (VFD) to pump. It is out there - Ask at an industrial electrical supplier
- Commercial EMI suppressor filter on power (mounted on inside of box to keep EMI inside the case) This was 110V in my case but a different version for whatever V-DC you are running
- Ground rod at the Hammond box. Tried an isolated ground installation (orange 15A plug) but eventually bonded inside and outside grounds
I do have to say that I have tested MANY brands of Switching Power supplies and the quietest Switching supply I have seen is the Alinco DM330 series that Ray K9DUR mentioned in a earlier post, I use the newer one that has the USB charge port on it and I really like the DM330 for being dependable and RF quiet.
The big difference you will see with one of the Linear power supplies is there weight and how much current they draw from the AC lines compared with the switchers.for the same DC loads.
I had a Astron 35 Amp Linear power supply before the Alinco switcher on my radio station here and my power bill was $12.00 on average higher then with the Alinco switcher.
I have tested the following Switching Power supplies with the highest HF RF noise first. 1 being the worst in my test.
1: Astron RS35
2: Ameritron / MFJ early model of SPF75 , MFJ4275, MFJ4245 all pretty noisy.
3. Jetstream JTPS75BCMMKII (basicly the same exact unit as the Amerton and MFJ4275 but not as noisy.
4. DuraComm LP-25
5: Samlex America SEC1235M< Almost as good as the Alinco DM330 but does have some RF hash.
6. Alinco DM330FX, much much better then the rest of the pack and it does have a knob you can adjust just INCASE you have a little spike on your operating frequency, but I have never used it here.
Hope this helps and of course your milage will very
I do have a switcher that I used in the past. Its a power-werx SS-30DV. The darn thing is pretty quiet and I would highly recommend it. Very small, light, efficient and doesn't create a bunch of heat like the linear supplies. I have an older Astron linear supply but I never use it any more. Big, heavy, creates a bunch of heat and uses a lot of power just sitting there doing nothing.