Saturday, 15 June 2013

Converting a HP DSP-600PB server power supply to run as a 12v 47A bench supply.

I've used several ATX supplies for radio use, but my latest aquisition of a Yaesu FT747GX needs over 20A.  more than the 15A  available from the ATX.

someone on the Hamradiodeals forum suggested a server supply, so a little googleing for info, and a glance at ebay got me a HP DSP-600PB for £13 delivered.......

there is no NEED to take the top off other than to remove the locking bar with the red knob shown at the top of this pic.

I used Futaba RC plugs to access the 12 pins.  I COULD have soldered direct, but this was going to be awful fiddly, and I had a box of random Futaba bits......

so far I only want 4 of the 12 pins.

numbering them like this.....


4 & 8 together lower the fan speed. 

6 & 10 together, and connected to the other two switch the whole thing on.

you COULD put a switch on there if you wanted.

I don't want one, so I just twisted those 4 wires together and soldered them

there are other things you can use the other pins for, so I'll keep those available, just not used now. 

connecting to the spades is a little akward so I made some pins by stripping back some insulation.....

then tinning it to make it rigid so I could push it in between the spades and then soldering it in place.

repeat for the other wire, plug it in and she's a go!

1st QSO was with OE1LZA, Laila, who gave me an all clear on audio.  6 more QSOs around Europe mean all is fine and dandy.

thanks due to:


for the info I used to make this happen.

New rig day!

OK, it's new to ME, not new from the factory.....

a Yaesu FT 747GX

its a mobile rig so it needs an external power supply.  I STARTED with my atx supply salvaged from a PC.

According to the sticker on it, it's good for 15A.  Sadly the 747 needs 20A.  

When I first fired it up with the ATX, it was able to tx on cw and SSB but the report I was getting back were poor.  if the CW drive was past 9 oclock (about 25%) ot was distorted, and if the SSB mic gain was above the same.... guess what?  distortion again.

so rather than spend £100 of a scary big power supply, someone suggested a server supply..... allegedly good for 47A at 12v.......

next post will be a stand alont tutorial on that, but for now, it's all working well and I'm a very happy bunny!!

Friday, 7 June 2013

latest long DX....

ZP6CW Paraguay
LU7HF Argentina

So the top twenty distance now stands at......

ZL2IBF New Zealand 11381
LU7HF Argentina 6805
ZP6CW Paraguay 6310
PR5B Brazil 6243
PP5EG Brazil 6219
HS5NMF Thailand 6069
OA1F Peru 5971
PY2EX Brazil 5927
PY4HO Brazil 5734
JA7QVI Japan 5729
HD2A Ecuador 5699
PY4RGS Brazil 5624
PP1CZ Brazil 5566
PW7T Brazil 5214
N2PW USA AZ 4936
HK1NA Colombia 4776
PV8ADI Brazil 4705
PY7PZ Brazil 4647
YV5DTJ Venezuela 4599
PR7AR  Brazil 4582

The ~2 and 3 places were on 12 & 17m so the long wire.......

Saturday, 1 June 2013

I've just got an email from Martin at the European CW Association about my entry in the QRS activity week last month.

I've only gone and won!!

my first certificate for the wall......

full results here:

this evening I was heading off in the car to collect one of the kids from the cinema and turned on my radio.   

I drove along chatting to MM6CTH (Shane) through the GB3NI repeater.  in front of me, stopped at a level crossing was a police patrol car. The gates lift and we drive off with me still chatting away to Shane.  At the traffic lights 1/2 a mile further on the blue lights go on and the Officer from the passenger side gets out and comes to the drivers door.

ALWAYS be polite with the good folks of the police of course

are you taxiing?  he asks..... (no taxi plates so he'd have had me there.....)

"No its Ham radio" says I, "Callsign MI0OIM, and it's legal for me to use it as I'm driving"

"are you sure" he asks, so I explained how the law on phones doesn't apply to microphones so that he could use his radio mounted on his stab vest.  Unfortunately, I didn't have the actual letter of the law off pat, but I told him that all was fine and dandy and while if I was driving dangerously as a result, then certainly I was open to prosecution, but not for simply using the mic, as it was fully legit.

I suggested that he take a record of my reg no and if I was wrong to please get in touch, but it IS right, really.

Poor guy was bewildered.  obviously there are too many laws for an officer to know them all, and in future I will have a copy of both my licence and the relevant law (below) in the glove box of the car, for back up, but he went off dubious but (for the time being anyway) happy!

The Road Vehicles (Construction and Use) (Amendment) (No.4) Regulations 2003 Statutory Instrument 2003 No 2695