Portsdown DMM Display and Logger

[G8GKQ]

I have just updated the Portsdown 4 with the full release of the Digital Multimeter (DMM) Display and Logger.

This uses a cheap DMM from Lidl with a modification for serial output. The main application is for rechargeable battery capacity testing. Full details can be found on this Wiki page: https://wiki.batc.org.uk/Portsdown_DMM_ ... and_Logger

This version only works for the DC Voltage range on the meter. I will add other ranges in due course. I also hope to be able to add support for the USB-connected Maplin/Precision Gold N56FU meter (about 15 years old?) when time permits.

No other Portsdown functionality is affected by this update, so no rush to update if you are not wanting the DMM mode.

Please report any bugs or suggestions for improvement here.

Dave, G8GKQ

[radiogareth]

Lidl currently have good stocks of the DMM suitable for this conversion, other than the cheap PVC test leads its a very nice DMM for an 'auto ranger' - I used to have some Flukes which were DIRE from a usefullness point of view. There is also a nice box of heat shrink tubing in a range of useful sizes and colours, some velcro ty-raps (seek out the longer colourful ones, 300mm x20 for £1.99) which I find great for /P cable bundles as they are long enough to go round the antenna boom and/or the mast once the cable is unwound.
Note that the coax stripper is for 75R varieties.
And all sorts of other things you didn't know you needed
Gareth (now with 2 boxes of heat shrink, one from last year and one from today....)