Re: Launcher relay question

In article <11smde4tpf1g215@xxxxxxxxxxxxxxxxxx>, the notorious t-e-d <tdstr@xxxxxxxxxxxxxxx> writes:
> Ok, I'm just about to start the build on a 12v relay launcher and I'm
> running into trouble. In particular the relay unit. I've checked damn
> everywhere locally and have not been able to locate a suitable 12v SPDT
> relay. Found plenty of 12v SPST relay units but no SPDT units. I've
> checked several auto stores and surplus stores to no avail. I ended up
> buying a 12v 30 amp SPST relay at rat shack and I have no doubt it'll
> work just fine but I'd *really* like the feature of a continuity check.

I just took apart my old (late 80s?) relay box. It has such a relay. It's
labeled Auto Spec TW-3415. But a web search doesn't find any references.

I did a search on "RELAY 12V 30A SPDT" and got a LOT of hits, including
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=330-070. I'd
start looking locally at car stereo shops, which is where I think mine came
from.

While my relay design uses a SPDT to drop the continuity check when I
launch, I don't see why it wouldn't work with a SPST relay that just
bypasses the piezo buzzer the same way the Questes launchers bypass the
light bulb when you launch.

--
Bob Kaplow NAR # 18L >>> To reply, there's no internet on Mars (yet)! <<<
Kaplow Klips & Baffle: http://nira-rocketry.org/Document/MayJun00.pdf
www.encompasserve.org/~kaplow_r/ www.nira-rocketry.org www.nar.org

Vulcans believe peace should not depend on force. -- Amanda, "Journey to
Babel," stardate 3842.3
.

Relevant Pages

  • Re: Launcher relay question
    ... In particular the relay unit. ... I've checked damn everywhere locally and have not been able to locate a suitable 12v SPDT relay. ... I've checked several auto stores and surplus stores to no avail. ... light bulb when you launch. ...
    (rec.models.rockets)
  • Re: Launcher relay question
    ... not sure why you couldnt find a SPDT relay. ... everywhere locally and have not been able to locate a suitable 12v SPDT ... Found plenty of 12v SPST relay units but no SPDT units. ... bypasses the piezo buzzer the same way the Questes launchers bypass the ...
    (rec.models.rockets)
  • Re: Launcher relay question
    ... In particular the relay unit. ... I've checked damn everywhere locally and have not been able to locate a suitable 12v SPDT relay. ... light bulb when you launch. ...
    (rec.models.rockets)
  • Re: 12 volt Home electrical system?
    ... The relay then latches magnetically and needs no more input power. ... The switches also went bad, ... I didn't know they made SPDT doorbell buttons. ... The switches, actually breakers, were far from the rooms. ...
    (alt.home.repair)
  • Re: Launcher relay question
    ... If you cannot find the SPDT relay, you can always spring for a DPDT. ... In particular the relay unit. ... Found plenty of 12v SPST relay units but no SPDT units. ...
    (rec.models.rockets)