classic motorcycle forum

Motorcycle Discussions => European and Other Bikes => Topic started by: R on June 26, 2021, 02:24:32 AM

Title: Jawa electrical gizmo ?
Post by: R on June 26, 2021, 02:24:32 AM

I've got amongst some stuff a Jawa battery box.
Looks like plunger frame era, early 1950s, bit crusty ?
Its got an electrical gizmo on top that could be a zener diode maybe ?
Labelled as USMERNOVAC JAWA  6V 1.5A

Anyone shed any light on this ?
9w doesn't seem like much to do anything useful with ?
Unless its quite a low output electrics all around !
There is a bit online on this - but its all in czech !

(https://i.postimg.cc/RFy5dfN1/Jawa-electrical-fitting2.jpg)

https://i.postimg.cc/MZf8TsF9/Jawa-batterybox.jpg (https://i.postimg.cc/MZf8TsF9/Jawa-batterybox.jpg)

Title: Re: Jawa electrical gizmo ?
Post by: Rex on June 26, 2021, 08:33:31 AM

Can't you copy and paste the Czech stuff into Google Translate? Early 50s sounds too early for Zeners though. Maybe it's a half-wave rectumfrier?

Title: Re: Jawa electrical gizmo ?
Post by: R on June 27, 2021, 01:22:30 AM

You could well be right.
That may mean the bike ran ac electrics, and the battery was merely trickle charged - for parking lights ?
Villiers used a similar system when a battery was incorporated  ?

Good suggestion. I'm not even sure what language that is.
Last time I tried something like that, it made no sense.
Technical terms are often not in common translation usage /dictionaries.
I'll work on it.

Title: Re: Jawa electrical gizmo ?
Post by: Rex on June 27, 2021, 08:14:49 AM

Charging for parking lights sounds about right, as at a rating of 1.5A they clearly weren't expecting too much.. ;)

Title: Re: Jawa electrical gizmo ?
Post by: john.k on June 27, 2021, 09:25:22 AM

Tartan Manet scooter.