+- ARCHIVE: Australian Ham Radio Discussion Forum ( AHRDF ) (https://www.ahrdf.net/forum)
+-- Forum: GENERAL (https://www.ahrdf.net/forum/forum-29.html)
+--- Forum: Transceivers, Transmitters & Receivers (https://www.ahrdf.net/forum/forum-18.html)
+--- Thread: FT817nd acc socket 12v...current limit? (/thread-472.html)
FT817nd acc socket 12v...current limit? - VK3LU - 27-12-2017
Does anyone know the maximum current that I can pull from the 12v pin in the 8 pin mini din socket?
There is no mention of it in the manual that I can find.
73 Nev
RE: FT817nd acc socket 12v...current limit? - VK3ALB - 27-12-2017
Hi Nev,
I haven't found that info anywhere but I have had to repair several FT817 where the supply was missing from the connector. The culprit was a dead teeny weeny SMD 0402 10 ohm resistor feeding the acc socket. Had to pull the board out to find it.
If I do the maths on a 10 ohm 1/16th W resistor I calculate you wouldn't want any more that 8mA running through it for any length of time.
If you're up to it I'd consider this mod http://vk4ghz.com/ft-817-12v-acc-mod/ as a way of protecting your rig. You could add a low value, low power resistor in series with the wire for a bit of extra protection.
RE: FT817nd acc socket 12v...current limit? - VK3LU - 27-12-2017
Thanks Lou,
I was hoping it had a greater capacity than that!
I was thinking of using it to power an AH-4...Ah well, looks like an external source is the go. Probably safer.
You don't happen to know the current draw of an AH-4 do you? Icom say precious little about it other than less than 1 amp. Great help!
73 Nev
RE: FT817nd acc socket 12v...current limit? - VK3ALB - 27-12-2017
Hi Nev,
No idea about the AH-4 but you could always measure the current during a tune cycle. The tracks to the ACC socket in the '817 are pretty thin, good idea to power it separately.
RE: FT817nd acc socket 12v...current limit? - VK3AV - 27-12-2017
The Icom brochure for the AH-4 states in the specs section that the current draw is less than 1A.
Read here - https://www.icom.co.jp/world/support/download/brochure/pdf/AH-4.pdf
They are a great unit in my opinion. I have been using one on my ~40m horizontally mounted loop attached to Icom transceivers and it does a fine job.
Regards
Bernard
Sorry, I did not read the other thread post first...you said it was 1A.
RE: FT817nd acc socket 12v...current limit? - VK3LU - 27-12-2017
Hi Bernard,
I like the AH-4 too. I use it to match a 140ft dipole fed with open wire line. It's quick and gets the swr down to almost zero. It works seamlessly with my IC7300.
I am working out a way of using it with my FT817 for wspr. Just about got it figured.
73 Nev