Just my opinion, this is the best video on RU-vid for converting the HSTNS-PLxx. Just completed my first conversion of an HSTNS-PL18. After reading of people having the PSUs shutting down when run above 13.5 volts I elected to not adjust all the way up to 13.8. My 50 watt VHF radio drops the voltage 0.1 volt for just long enough for the DVM to read it and then comes back to13.5 v. I've run it for less than a half hour as I write this but us far it is extremely quiet. I keyed the mic with a dummy load on the radio and the fan didn't speed up after 30 seconds. That's about a 14 amp draw. For comparison, I bought a Chinese power supply thinking that it would be OK for a while but the noise was hard to ignore. My normal room sound level is 32 dB. When the Chinese power supply's fan came on the sound level jumped to 49-50 dB even when the radio was drawing less than 0.5A just listening. It's being returned to the people with the big blue smile on their trucks. Other than soldering on a near microscopic level it was easy. I spun a cheap 30 watt soldering iron tip against a bench sander with a drill to make a very fine point and tinned it. Rather than soldering a jumper to turn the PSU on I installed a toggle switch. The PSU is getting mounted in a vertical stack box that I'm building so the toggle switch and a power meter ("lipo battery watt meter" on Amazon) will be mounted up front for monitoring and convenience. That style of meter is powered by the PSU and doesn't require a shunt. They will handle voltages and currents far above what the PSU is capable of delivering and they're very inexpensive. Currently (8/2024) they're about $21 USD for two meters. I lacked the confidence and a small enough tipped solder sucker to try to jumper the discarded resistor just with solder. I tried to bridge the pads with a short piece of very small gauge tinned wire but it kept rolling out of position. Finally I had the idea to tin a piece of copper wire and flatten it before cutting a piece off to bridge the resistor pads. That made the task easy. I held the flattened wire in place with the tip of a long straight pin and it was soldered in about 2 seconds.
Good tip, they do the job. I have been using a 10 year old HP HSTNS-PR17 38 amp model that I dug out of the skip at work for my base PSU for the past 16 months, it's "serv"ing my radios well :D
Great video. I did this to two units just last week. Mine were the PD units so did the resister and trimmer trick. Worked perfectly and although I have not used it on my 7300, I do use them on some of my 10-meter rigs and one has a 200+ watt amp built in, and it runs nice without any obvious noise. Not very elegant but I soldered 8 gauge wire the full length both sides of the pcb on pos and neg to a distribution block. I was afraid of pulling the full potential current from just a small section available on the pcb and burn it off. That as well as reducing the chance of venereal.
Please use some fuses on the dc side. Murphy will otherwise come whack you for sure. Yes it is fundamental but not mentioned. Also, i would adjust under load if you have sensative equipment on the dc side. Ask me how i know ..... Murphy is a good friend 😂
I watched this video, ordered a HSTNS-PL18 for 20 euro on ebay and in 10min got it modified. It would be useful to get som ideas for housing it. Anyway many thanks Jonathan.
Hi Jonathan. I found that the unit shuts down at around 10 amps , Reset above 12amps PSU vibrates very loud. I dropped the voltage to 13.2V all OK . Great video.
13.5v is the sweet spot. Going upto 13.8 i found it cut out. Yet I had a different one that I used a 22k resistor across ground and the voltage pot. Work fantastic.
I have a mydel proper 50 amp power supply for cb and ham radio, And using a radio just putting out 50w the voltage drop is quite a lot 13.8v to 10v quite bad voltage droop for a proper shop bought supply. I also have a modified server supply that pushes out 13.8v and 82amps i run my Kl703 off it and even though its drawing lots more amps the voltage only drops to around 13v. I think companies like RM should also make power supply units that accompanies their amps and make sure they are up to the job. That would be a nice package option too. When buying a linear.
I get 8mm copper radiator pipe, smash it flat, fold in half and shape as desired, solder the ends to the upper and lower edge connector and then fit heavy duty terminal posts to your copper bar, use heat shrink over the exposed bus bar before soldering it on
I've been working on building a kind of backplane for these common slot server PSUs so that you don't need to solder to the connectors. It's basically a PCB with a connector that fits onto the PSU's edge connector and interfaces with all the different pins.
Looks like there are a bunch of different breakout boards for HP power supply connectors that you can pick up cheap; many with a voltage display and screw terminals. They seem popular in crypto mining community, and found a few that list your supply as compatible. They look like a neat solution to get radio equipment connected.
I got 4 Dell server PSUs that I intend to use in series to drive a future power amplifier. by exchanging some metal screws for nylon, I can separate negative from the ground.
I use an old power supply out a 1990's Compaq computer for 12V DC in my garage. It doesn't have enough amperage for a ham rig - maybe a CB since those are limited to 4Watts in the US. I use the power supply to run a car radio on a shelf, complete with a ring of speakers out of a luxury car for a surround effect. My garage is loud when I'm underneath a car. 😁
Bought two of these power supplies on Ebay. Tested fine. When I tried to bridge the gap the SMT Resistor came off. Replaced it and tried again. No luck. Pad had come up with the resistor. I mostly could not see the devices and even with a magnifying glass had a very hard time. I decided to toss the first one and give the second one to my friend. Too small, too much difficulty with temp control on the pencil. Not worth the effort if you are not equipped to do SMT soldering and have an electronic magnification system to work with. I will still keep to commercially made PS systems as I don't have to do anything to make them work but plug them in. Perhaps this might have been easier 60 years ago LOL!!! Too old for this shit!
Hi Jonathan I have makenone ans its providing 13,7 volts, but anytime I transmit with my radio, the PSU gives some strange sound, looks like the relé inside its Activated by the RF? Please any solution for this? Thanks you.
Hi thanks for the post 👍 Could you please tell after watching your video is bought exactly the same power supply I didn't modify it yet but when I plug the cable there's no led green light on and no output voltage does that mean it's arrived already faulty 🤔
Done this and works a treat, however I’m finding I’m getting slight electric shocks from me Radios coax when there connected to this supply, any thoughts why???
great video, some information, I bought the same model of power supply from ebay, I don't know if it is defective, not having an identical model, I will describe what happens, if I load a 300w medium absorption rx580 video card, I hear a strong internal electric hum and normal? then without any boot board connection, i just apply electric plug it starts the fan starts automatically, is this normal?
How it works when you plug some load? I suppose that rising voltage up works fine without load but what is happening when you draw several amps? I saw some videos when it shuts down automatically.
In my experience it turns off under load if the voltage is set slightly high. If it does shut off, back the voltage back slightly to say 13.5V when idle and it should be good.
