Bisistor ant-feedback unit

[peteleo]

Does anyone know what's the purpose or function

[peteleo]

https://www.ebay.com/itm/134004082053?s ... 1438.l2649

[Brett Wilkie]

I don't know for sure but by looking at the packaging it seems to be a device to isolate between two batteries, too bad there isn't a wiring diagram.

[Sideways]

A regular coil with some form of isolation as you suggest or just a coil with a fancy name?

[BigFred]

I have no idea if this is accurate, but I asked a friend to look at that ad and his guess was...

"Might be a variation of a ballast resistor. Looks like a coil. Coils usually have resistors built in, but some cars used an external resistor. Chrysler used them and so did Sunbeam and others. Many suggest them. They are designed to limit the battery voltage going to the coil other than when starting, which is when you need that voltage the most."

[peteleo]

Came across an article in Motorsport Mag that mentions the anti-feedback bisistor. Meant rather for a RV.

https://www.motorsportmagazine.com/arch ... indscreens

[Sideways]

I have been vainly dredging the memory to try to recall if the FFR Land Rovers I wandered the hills and dales of Yorkshire in back in the '60s had these devices fitted.

Don't believe so but...

The RAF FFRs (Fitted For Radio and thus 24V electrics) did have "something" to isolate the batteries but I believe the vehicles were 24V throughout, starter, alternator, lights etc.

Or not, it was a while ago.

Tis all a bit fuzzy but I did "appropriate" a few 24V panel bulbs used in the ATC Tower instruments which were a pleasing shade of red and used I them in my gauges in the Mk1 Cortina GT. Since they were 24V and being run at 12V in the Cortina the gauges were perfectly back lit (no instrument dimming available back then) for night driving.

If any/all of the above is incorrect, I blame it on the weather, memory and social unrest.