go to minute 29:40 to see how it behaves (and heats) with 12V in, 5V out and 2A to 3A load...
unfortunately he doesn't measure the output ripple and/or noise (the switching frequency should be 180 KHz).
On another note why is it, that the leads, switches, connectors etc always seem to be the most costly part of any build ? Needed some 8mm 2.5mm standoffs ended up paying over £3 for 10 ! Really need some more old junk ex equipment to strip down for cheap parts, stroll on when rallies start up again
As I would generally be using it portable, I wanted a stable bias voltage, so didn't use the input supply as that could be all over the place. Instead I tapped off the on-board 5 volt regulator via a multi-turn pot. My unit didn’t draw the same amps as Jims, but it did deliver a very handy 11 watts or so, with a bit less for DATV use. As it had no output filtering, I wondered if one of the cheap low pass filters from eBay might survive. Testing one showed it got slightly warm but no visible duress shown(i.e. no magic smoke) so I cut off the input SMA, used a decent silver mica coupling capacitor (the one fitted was a tiny 200pF ceramic) and removed solder resist as required to solder it down to the motherboard (LHS) and solder tabs under existing screws (RHS). A handy little unit to go lightweight /P with (DATV SOTA??) or to use with the Langstone.
I've also managed to GPS lock a 40MHz oscillator for the Pluto (not installed yet), and get an EPS32-CAM board working which may be fun with the Portsdown in due course. This lock-down business is certainly helping me knock a few items off the Project List
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Getting there slowly John
https://www.ebay.co.uk/itm/SP7T-DC-6GHZ ... 2749.l2649
Its actually for remote switching down my garden rather than my Langstone, but if you are building a 7 band go-box you might like one too. Hes got loads of nice stuff listed and is clearly amenable to a deal.