was NOT expecting to find a PRO III board, so old it might be broke and I cannot remember. These must be good for a 1 Watt 30min fun session, at least these ones are both super clean spurious free PLL's, if they even work that is. I will have to find out into a dummy load some time.

Can I make them stereo somehow that would be the dream. Will the mono input on either of them take whatever come out of a stereo encoder ? I am so clueless about stereo on rigs sorry.

What is the one on the left? ....Is that the PCS Electronics driver?

Hi there yes I think it is 2015+ PLL 15 Watt and next is the NRG which I guess I had in the box the PCS is now mounted in. I have a vague recollection something may not be well with the NRG. Only 1 way to find out at some stage I will work out what is what. No big plans but it would be nice to write working or broke on them in case, something nice about having at least something that works.
Maybe stereo is nothing to concern about for a 1 Watt hobby hero. I have never done stereo much so it has some curiosity.

I take it the input needs a 40khz bandwidth on its input to understand the stereo components in the unbalanced audio connection ?

NRG must be well old cause I built it and cannot even remember I did, otherwise there would not be a tick beside every component on the A4 sheets I do know it did work after i built it but maybe something went wrong later.

I swear i had a PCS somewhere in a different box. If I find that I will also post a pic, I recall a die cast aluminum case, it may have been dumped in a clear out that would have been a bit silly unless this is the one that i put in another case, this case looks like an old stephen moss VFO baked bean can shielded rig from the 90s, I will test things when I can and keep digging in the old shed boxes.

it should be pcs 6xxx series. The 2015 does not have a variable capacitor for fine-tuning the reference xtal. also in 2015 there is no shield on the circuit board around the vco stage.

PS. both boards are ready for stereo. someone already gave you advice to take off the emphasis jumper and there is no reason why it shouldn't work. bandwidth up to 53khz is required, but that information is not important to you now. you have on ebay a cheap clone of the pira stereo encoder which is ok or install the pc application. more or less every newer PC or sound card supports 192khz sampling rate and that is the only prerequisite for the experiment.

I will see if they fire up into a load at some stage thanks for info.

Wow the memories nice warm transmitters, transmissions, coming over the airwaves, hazy sunny days that went on forever. To accept a stereo encoder disable the preempis jumper, make sure you keep it or leave it over one leg, they have a habbit of running away. It was great fun did think about putting my old playlists online, still got all the music in me, sounds like folks would knock at your door for doing this now. I could look at the internal routing on my windows laptop maybe see how I got stereo tool working, suspect you don’t have an encoder.

Years ago it was the nrg their stereo encoder, winamp using sound solution..none mp3 files would just pass through it neat, thankfully mp3’s became the default, some would come over low volume, thankfully car radios were good then and cope with it, you would want some crackles over the top of it, it builds character.

Nice northeast, I remember only a specific old broken laptop output would drive the pcs with winamp and the extra boost volume up. pcs seem to want a strong audio signal, more than anything I had could produce other than that laptop. When I get a chance I will see if they work. It would be for a little 1/2 hour once in a blue moon and that's it. That's all you can do really without getting the fear, first you get a buzz then the fear comes, just how they want it to be. I have no interest to have an actual station at all, it is just that occasional feeling you want to have the radio buzz, just to remember the feeling.

FMEnjoyer wrote: ↑Sat Mar 29, 2025 4:39 pm was NOT expecting to find a PRO III board, so old it might be broke and I cannot remember. These must be good for a 1 Watt 30min fun session, at least these ones are both super clean spurious free PLL's, if they even work that is. I will have to find out into a dummy load some time.

Can I make them stereo somehow that would be the dream. Will the mono input on either of them take whatever come out of a stereo encoder ? I am so clueless about stereo on rigs sorry.

A simple standalone software based rds and stereo encoder like Airomate is suitable as long as you have a 192khz bitrate capable soundcard. The cheap usb ones cost about £8

The Pro III will take stereo if you take the pre-emp jumpers off, NRG used to sell a stereo coder for it. No idea about the PCS, with the number of chips it might have stereo built in already

Doubt anyone will bother you over a little 1w rig from the attic, I've done worse before and I'm still here. Ofcom don't give a shit nowadays unless youre sprogging on one of the big boys. I say stick a dipole up and see how far it goes, just pick a clear freq and keep your mod level under control

You can have one of my stereo boards if you want some hardware to play around with. Pm me if interested

viewtopic.php?t=3388&start=40#p40121

They look sophisticated, thanks for the offer, I will see what is working. I have some memory of a 1947 being purchased way back so it could be that the NRG is defunct, I vaguely recall taking a GPA down once made from coat hangers and the main element no longer being attached, coat hanger wire being inflexible and transferring all stress to the solder joint, that would almost certainly do no rig any good at all.

The thing that gets me going is putting a few 100mw, let's say 100mw - 500mw station on a fibreglass flag pole up high, with everything on the single mast, power-rig-audio-wire for antenna, no coax, no loss, no SWR worries, as such low power will not likely burn a transistor out. All these PLLs need coax and 12v so it means that is impossible. It is why I had a thing for those tiny Chinese things for a bit. I am fascinated by how far you can get miniscule power to go.

Looks like old PCS MAXPRO6000, slap nice stereodecoder front of it, or run Airomate whit small buffer amp between soundcard and rig.

What I remember, it wants around 0dB input level on audio.

Btw, You can easily feed audio and power on same lead on low powers.

SLA alarm battery, solar panel and a cheap eBay solar regulator will do for 12v in remote locations. Pro III board is a bit on the big side I take your point but theres smaller drivers out there. I like the Zozo 1w board, you can find it on here if you search. For a while someone was selling them prebuilt on eBay, not sure if they're still listed or not. It wants 15v to do the full 1w but at 12v should give 0.5w or so which I guess is exactly what you want.

Starting to sound like a nice little weekend project. Stick a driver, battery, solar reg and MP3 player in a waterproof project box and see what you can do. BNC or SO239 on the top, aerial could plug straight in, slim jim out of ladder line would be a good fit. Probably want to use a metal box for the rig if you're putting it so close to the aerial. Personally wouldn't bother with stereo for such low power, it wouldn't go very far

Frequent Lee wrote: ↑Sun Mar 30, 2025 11:35 am The cheap usb ones cost about £8

Managed to find one on eBay brand new for £2.99 a few years back which did the job.

NRG Pro III lives ! PLL locked with a quick turn of VC1. Measured using the worst power meter known 2.6W and 0.4W. At least there is RF and a carrier into a load.

The station on a stick idea had legs when it was off 5V, though of course I did not think through every detail, it would be a put it up at dusk in the woods get the next day approach. Solar a bit tricky for me. Even the USB C Chinese ones are total trash. I am still pssed off they cannot just get one of those chips right for 100mW. I have parked that idea myself now. Stereo probably not sensible, though I do know 80mW measured as measured on the 40 year old terrible meter does a mile and I know that can 100pct be improved upon. I suspect my meter is under reading a bit.

At least I have something clean for bit of random fun now And if I want I can do 2-3W up coax outside when I want to be a power station.

Was just reading this review on the PRO III, what a technical achievement, I know Albert is always saying so and it really was due. Amazing spectral performance I think. I only had a little 12v battery to test so power output probably about right, more than enough at 1/2 a Watt. Good feeling to know you won't annoy anyone with a clean spectral output.The board does look like from another era of electronics but we know that was all part of the design consideration then.

https://radio.xtreamlab.net/nrg_pll_pro3_review.html