What power supply do you use to power your rig? - Page 1
Forum section: electronics / rf-microwave

author: deephaven
author_rank: Frequent Contributor
timestamp: October 03, 2016, 12:40:14 pm
content: I'm contemplating getting an HF rig (100W o/p) but it will need a 13.8 volt power supply. Are there any recommendations? I'm trying to find one with over-voltage protection so that the rig doesn't blow up if there's a PSU fault

author: setq
author_rank: Frequent Contributor
timestamp: October 03, 2016, 12:48:25 pm
content: I use a 2/4A one of these for any radio stuff I do (mainly low power). Not terribly engineered. Basically a transformer, bridge, big smoothing cap and discrete regulator with a standard 2n3055 as the control element. It delivers what it says on the tin. It doesn't have overvoltage protection however:https://www.rapidonline.com/voltcraft-fixed-voltage-linear-power-supply-bench-526121Pick one conservatively based on the current you want to pull.Ultimately, do you really trust a power supply to self-manage its failure? I wouldn't! I'd stick an SCR based crowbar on the output and an inline fuse between the power supply and the crowbar. The SCR will clamp the voltage low and blow the fuse if there is a failure, saving your equipment.

author: voltz
author_rank: Frequent Contributor
timestamp: October 03, 2016, 09:19:00 pm
content: Hi, the PSU needs to be able to supply at least 20 amps. Preferably more like 25-30. But 20A is a standard current draw for 100 watt HF rigs.Over voltage protection comes in two flavours, crowbar (brute force shorting of the output terminals leading to blowing an internal fuse) or an over voltage sense circuit which trips the supply relay killing the PSU until a reset button is pressed.There is a wide choice of PSUs on the market. Some are massively expensive, others are quite cheap around £100 but need modifying to bring them up to a more professional standard. As you say, you dont want to risk blowing up an expensive HF radio for the sake of a few pounds to upgrade the PSU. There are plans on the internet for doing this. Like fitting a quieter and more efficient fan, better heatsinks, better RF suppression and over voltage sensing. etc.I cant recommend any particular type, many PSU are identical inside but have different branding labels, but i hope this info gives some general pointers to look out for and consider.

author: David Hess
author_rank: Super Contributor
timestamp: October 03, 2016, 11:26:26 pm
content: I have a big linear Astron for all of my radios but would consider any fixed 12 volt supply that has service documentation available. A more economical option might be to find a used Astron or similar and refurbish it yourself.

author: GreyWoolfe
author_rank: Unknown
timestamp: October 04, 2016, 01:04:02 pm
content: Quote from: David Hess on October 03, 2016, 11:26:26 pm+1 on the Astron, they are nice power supplies. Both of my current radios have built in power supplies but when I had my Kenwood TS-850, I used an Astron RS-35M. I powered the 850 and my 2 meter radio. I now use a RS-12A for my 2 meter base station and have a VS-35M sitting on my workbench that I won at a club Christmas banquet. On the RS-35M that I sold and the VS-35M, I did the inrush current reduction mod shown here,http://www.repeater-builder.com/astron/inrush/astron-surge.htmland added a bleeder resistor. I also replaced the bulbs in both with 110 degree wide angle white LEDs after one of the bulbs burned out on the RS-35M. If you want to do the LED mod, I found that taking power from the output will shut off the bulbs a lot faster than using the voltage source the bulbs had. With the original source, the LEDs would take about 45 seconds to a minute to go out, taking the power from the output, the LEDs go out in a few seconds as the bleeder resistor drains the main filter cap.

author: deephaven
author_rank: Frequent Contributor
timestamp: October 04, 2016, 01:34:45 pm
content: Thanks for all your comments, guys. I think an external crowbar would be a good choice as it will be something known - and tested!

author: donmr
author_rank: Regular Contributor
timestamp: October 04, 2016, 05:47:58 pm
content: I use an AGM battery and a Charles brand charger. This brand is a simple analog charger with no LEDs, uProcessors, etc. and thus produces very little RFI. The charger can deal with you drawing power as it is charging.

author: David Hess
author_rank: Super Contributor
timestamp: October 04, 2016, 07:28:11 pm
content: Quote from: GreyWoolfe on October 04, 2016, 01:04:02 pmThey are ok and I just used them as an example because they have service documentation available at least for their linear ones which use pretty standard discrete pass element LM723 designs with foldback current limiting and output thyristor crowbar protection. If I have any complaint about them, it is that they should put plastic caps over the exposed TO-3 power transistors on the back because if the shield of a connected coaxial cable touches them, bad things™ are likely to happen.

author: setq
author_rank: Frequent Contributor
timestamp: October 04, 2016, 07:52:46 pm
content: Those cheap voltcraft ones have covered transistors and a big warning sticker!No LM723. They appear to have designed their own one with discretes.

author: deephaven
author_rank: Frequent Contributor
timestamp: October 05, 2016, 01:07:34 pm
content: Anyone had any experience of using a switch mode PSU while operating on the HF bands? I was looking at the MyDEL MP-30SWIV which is reported to have over-voltage protection. The "Noise Offset" control might be a bit of a giveaway!

author: David Hess
author_rank: Super Contributor
timestamp: October 05, 2016, 03:08:16 pm
content: Quote from: deephaven on October 05, 2016, 01:07:34 pmA "Noise Offset" control is suggestive about the difficulties involved with powering HF gear from a switching power supply. I assume the control varied the switching frequency to move noise away from the RF channel being used.Some switching regulators are specifically designed to keep switching noise away from the 455 kHz IF and AM broadcast bands.Commercial HF transceivers have gotten away with integral or external switching power supplies from the manufacturer but I do not know if special precautions were taken or if they were just low noise.

author: AF6LJ
author_rank: Unknown
timestamp: October 25, 2016, 03:56:14 pm
content: Quote from: David Hess on October 03, 2016, 11:26:26 pmI have used many different power supplies all but one were linear.The current supply I am using is an Astron 25 amp linear supply.They are bullet proof....As an example of the above statement, a friend WA6MHZ had an Astron 35 amp supply backing up a large Gel Cell.... I was helping Pat one day do odd jobs around his shack and I asked about the 2 meter simplex radio he had set up, why it was not working...His reply "it quit working sometime last year, I haven't got around to finding out why". Well it was still turned on and so was the power supply running it, that is when I found out about the Gel Cell it was hooked across. It seems sometime several months back the battery shorted. The Astron was running into a dead short for something like nine months...I removed the battery, cycled the power on the supply and all was good again.Yah Get an Astron Linear supply.The switchers have OEM modules in them.I don't trust them as much.

author: deephaven
author_rank: Frequent Contributor
timestamp: October 25, 2016, 05:54:32 pm
content: Thanks for that great story, Sue. I'm surprised that there wasn't a hint of a smell having that powering into a short circuit for so long. Maybe it has fold-back current limiting?Altron is less common in the UK, but I might be able to find one.

author: David Hess
author_rank: Super Contributor
timestamp: October 25, 2016, 08:18:59 pm
content: Quote from: AF6LJ on October 25, 2016, 03:56:14 pmThe Astron 723 based linear power supplies implement foldback current limiting so it is not surprising that they can survive an indefinite short.

author: AF6LJ
author_rank: Unknown
timestamp: October 25, 2016, 09:29:15 pm
content: Quote from: David Hess on October 25, 2016, 08:18:59 pmThe heatsink was so hot you couldn't hold your hand on it....The surprise was that for as hot is it was, it worked just fine...Those are bullet proof designs...

author: David Hess
author_rank: Super Contributor
timestamp: October 25, 2016, 11:35:51 pm
content: Quote from: AF6LJ on October 25, 2016, 09:29:15 pmThe only thing required is sufficient power derating, which is easy to control with foldback current limiting, at the maximum expected operating temperature. The almost literal rule of thumb is is that you cannot continuously hold a thumb or finger against about 75C which is a pretty reliable case temperature for a power device so just being that hot is not a big deal.Better of course is to also include thermal protection which I do not see on any of the schematics for the 723 based Astrons but I did confirm the use of foldback current limiting. One thing I notice is that they all use the same pair of 2N3771 pass transistors from 12 to 70 amps; I wonder if Astron grades them and puts the best ones in the highest current supplies. Their frequency compensation is also very conservative.

author: deephaven
author_rank: Frequent Contributor
timestamp: October 26, 2016, 09:06:57 am
content: Do the Astron units have over-voltage protection?

author: msraya
author_rank: Unknown
timestamp: October 26, 2016, 09:37:37 am
content: I use a commercial cheap Diamond GZV-4000 for 5 years and no problem, It can power two rigs, not heat. No RFI nor hash.Only I change fan to another no noisy computer cheap fan and no noise from fan.ManuelEA7EE

author: AF6LJ
author_rank: Unknown
timestamp: October 26, 2016, 02:53:25 pm
content: Quote from: deephaven on October 26, 2016, 09:06:57 amYes most models do, you can find some that do not, some of the older ones.

author: SeanB
author_rank: Super Contributor
timestamp: October 26, 2016, 07:53:47 pm
content: Quote from: David Hess on October 25, 2016, 11:35:51 pmI would think not, just use a bigger heatsink for the higher power units, with the upgraded transformer, bridge rectifier and smoothing capacitors. I would also guess on the units over around 30A there will be 3 or more power devices in parallel, either by just modular placement of the same smaller heatsink plus 2 transistor and emitter resistor block, or a bigger number of devices on a common heatsink.The drop off of gain in a power bipolar transistor is not easy to select for, it will almost always drop to a low level ( some will actually have a gain of less than 1 at some point) at high current, so the only solution is parallel units so each has a much lower current flow, or use a really large die which has the same reduced current per unit area of silicon. 60A with 2N3773 transistors in switching needs around 20 parallel devices to get any hope of getting the drop down to the lowest levels, and driving the base with around 15A to get it there.

author: djacobow
author_rank: Super Contributor
timestamp: November 15, 2016, 03:40:21 pm
content: No love for the switchers here, eh?Well, I have a powerwerx sps-30-dm. It works fine. It is very compact. It does not generate hash on the amateur bands. It has a fan that comes on under load, but my rig's fan is louder.I hadn't really considered the possibility that the PSU might fail and take the rig with it. That would be unfortunate. Is this a common failure mode with switchers, like the output get stays stuck on?I also have a REALLY cheap Pyramid psv-300 that in use to power a 2m rig. Build quality is pretty bad, but no problems. Radio is cheap TYT so destruction would not be a tragedy. Actually, pretty happy with the setup.

author: CJay
author_rank: Super Contributor
timestamp: November 15, 2016, 03:47:41 pm
content: There are plenty of tales about converted server supplies being excellent for use on amateur bands, bearing in mind they can be used to power many tens of thousands of pounds worth of server they tend to be rather well engineered and I am lead to believe the HP ones are really rather good in terms of RFI

author: FlyingHacker
author_rank: Frequent Contributor
timestamp: November 16, 2016, 05:43:13 am
content: Check reviews in eHam.net. Many modern switching supplies get top ratings for use on HF. They also use way less energy for something that will be on a lot.

author: borjam
author_rank: Unknown
timestamp: November 16, 2016, 08:44:25 am
content: I've got two power supplies. A Daiwa SS-330W and a Grelco G1320M.Grelco is a Spanish manuafcturer of power supplies, and their linear series has been well known for 30+ years. It's a rather simple design with 2N3055 transistors for regulation and a crowbar over voltage protection.I got the linear power supply because for now I am using a window antenna and the switching power supply is a bit noisy. The linear is, of course, radio silent. The downside of the linear supply, it's large and heavy.

author: TheBay
author_rank: Unknown
timestamp: November 16, 2016, 02:27:14 pm
content: Microset PT-135 35a Linear here, VERY happy with it.There is a long thread on here about a C.E.P. I bought

author: K2CK
author_rank: Newbie
timestamp: December 13, 2016, 05:37:18 pm
content: The Astron's are my go to power supply. The linear models are heavy and built like a brick outhouse. Plus they are straight forward to repair. They are a dime a dozen at most hamfests.Good luck,Scott

author: David Hess
author_rank: Super Contributor
timestamp: December 14, 2016, 12:39:51 am
content: Quote from: K2CK on December 13, 2016, 05:37:18 pmI like that they are documented albeit poorly and maintainable.Big linear power supplies are simple enough that I am surprised there are no slightly less expensive "Heath" type kits for them but I guess there is not enough demand to support that kind of market anymore.

author: The_Penguin
author_rank: Regular Contributor
timestamp: December 16, 2016, 12:16:25 am
content: Astron VS-35M here. Have had it since '89 or so.

author: JStevensAB9JS
author_rank: Newbie
timestamp: February 09, 2017, 03:44:33 pm
content: I am using an MFJ-4235MV switching supply for my Alinco DX-SR8 100 watt h.f. radio.John Stevens AB9JS

author: FlyingHacker
author_rank: Frequent Contributor
timestamp: February 09, 2017, 04:10:44 pm
content: This site has great info on the Astrons, including schematics:http://www.repeater-builder.com/astron/astron-index.html

author: tkuhmone
author_rank: Regular Contributor
timestamp: February 09, 2017, 06:26:07 pm
content: I have one HP server modular power supply - to be modified for ham radio power use. Few resistors at least needed, to get power sulply starting. It is SMPS type, so I am not yet sure if it generates some noise to HF bands (or any other). If there is too much noise, I will look at other power supplies...Also the output voltage is by default 12V. Need to check if it has a small adjustment - so I could increase voltage a bit up towards 13.8V DC. Current output on that supply is around 30...35 amps.

author: deephaven
author_rank: Frequent Contributor
timestamp: February 15, 2017, 05:47:32 pm
content: Well, I went ahead and got hold of a Mega Watt psu - that's the make, not the power rating!It powers my IC-7300 rig nicely and, even though it's an SMPS, there is no sign of any interference on any of the bands. It's light and compact and does have a fan, but that's not too loud.

author: worsthorse
author_rank: Super Contributor
timestamp: February 16, 2017, 08:53:01 pm
content: Samlex 1223 (no meters) or 1235 (has meters). Delivers to specifications, no EMI issues. Only hassle is the weird connectors rather than real post connector but there's an Anderson Power Pole hack that works nicely and fixes that.

author: tkuhmone
author_rank: Regular Contributor
timestamp: February 16, 2017, 09:37:15 pm
content: Quote from: wch on February 16, 2017, 08:53:01 pmMy previous company ham radio club had a one "field day setup" that could be taken into lending. It had Samlex power supply, powering IC-706 rig. I am not 100% sure of the model anymore - since I do not have access to setup anymore. It most propably was 1223 model (at least google image search match to supply). That model what was included in the setup, was a really bad example how many RF-spikes were generated. At least in 80m band, there was typically seen many spikes in the spectrum, typically 30...50kHz between each other. When same rig was switched to 12V battery use, spikes disappeared.I quess it might have been multiples (?) of a switching frequency of not properly filtered SMPS were radiated to antenna (ie windom). In the time these was modifications instructions available for that supply - since that unit was not my own, those modifications were not done...EDIT: link to Samlex-1223 mods below. I have not used new models of Samlex 1223 - cannot be sure if the issue been already correctedhttp://oz1db.dk/samlex/start_eng.html

author: worsthorse
author_rank: Super Contributor
timestamp: February 17, 2017, 04:12:34 am
content: I have schematics for the newer models which have bypass capacitor installed. Using it with two HF rigs, no emi to speak of. YMMV, i imagine...

author: AF6LJ
author_rank: Unknown
timestamp: February 20, 2017, 03:37:55 am
content: Quote from: wch on February 17, 2017, 04:12:34 amI have one that I repaired back in December, works great I also don't like the connecting scheme for the DC...

author: jadew
author_rank: Frequent Contributor
timestamp: March 01, 2017, 04:43:59 am
content: I have a Hoxin TD-14SS30. I haven't noticed any noise.It was the cheapest option available to me when I bought it, but so far it seems decent, haven't opened it up tho.

author: Chig
author_rank: Contributor
timestamp: March 01, 2017, 12:28:45 pm
content: I have:Manson ~3-15v 40amp switcher, which currently just runs some LED lighting outside.Powerwerx SS-30DV, which definitely has RF hash on it (i hope to resolve this, as it's a good compact supply otherwise), but is just manageable and runs my FT-991Powerwerx SPS-30DM, which also has RF hash on it, and again, hope to resolve, as it's a decent variable.Not powering any rigs currently is a small lab supply, a Trio PR653, but also needs some work for reliability (has a sticky relay i think).Plan at this stage is to build a 25-30 amp linear, but want it to be as safe, reliable and well designed as possible... Watch this space?

author: brobers
author_rank: Newbie
timestamp: March 06, 2017, 06:38:14 am
content: I use Astron 25A supply as my main supply for my day-to-day radios. Several years ago I ran a packet BBS on HF and multiple VHF radios plus TNCs. With the exception on the computer I ran this setup off a 12V deep cell battery and had a battery charger with a deep cell mode hooked to the battery. How I knew it was time to change the battery out was to listen to my VHF radio transmit every once and a while and if you could hear the AC hum you knew it was time for a new battery. Batteries lasted around 3 years or so. Not the best way to do it but it worked.

author: Unknown
author_rank: Unknown
timestamp: March 06, 2017, 06:52:49 am
content: Another vote for the Astron linear supplies (in any size). Built like bricks, they run forever.Also great customer service. I visited their Irvine, CA location once for a free repair to a supply that was DOA. Very nice people, and schematics are always included.

author: sgub
author_rank: Newbie
timestamp: June 09, 2017, 06:58:00 am
content: I use Yaesu FP-1030A (13.8V 25A) linear PSU for my IC-7000 HF radio. It's essentially a re-branded Diamond GSS-3000 (13.8V 30A) , with over current limited to 25A instead of 30A.