Single coil latching relay help

[electrosonic]

On my last smallbear order I bought, a relay to mess with. (Panasonic TQ2-L-9V ) it took me a couple of hours to figure out that is not a dual coil latching relay thus the the Geo latching relay driver can't be used to drive it. Can anyone point me in the direction of a simple circuit using a momentary switch to drive this.

(Searching the forums brings leads me to this dead link, www.geocities.com/transmogrifox/relay
if anyone give me a copy to look at it I would appreciate it.)

Thanks,
Andrew.

[composition4]

About to go out sorry, but have a read of H-Bridges

http://en.wikipedia.org/wiki/H-bridge

can make one discrete wit transistors or buy them in packages

If you need more help, yell out and I'll discuss further tomorrow

[R.G.]

This requires doing much what the latching relay circuit does, but pulling each side of the coil high/low as needed, and making that slow enough not to click at the same time. As noted, an H bridge driven by the slowing-down stuff should work, but it's about 2-4 times more circuitry than the two-coil latching stuff, and correspondingly trickier to get running.

It ... might... be cheaper to just take the price of the relay as a cost of education and reorder a double-coil-latching relay, depending on whether you want to learn about circuits or just get something to work.

Education is always expensive. Some times paying in money for it is the cheapest way. Depends on what you most want to happen.

[electrosonic]

What is the appeal of the single coil relay then? Is there any benefit to using them considering they are more work to use?

Andrew.

[R.G.]

The single and double coil relays are both useful. Which is most useful at the moment depends on what you already have. If what you have is a pair of signals that pulse for A or B, but are not otherwise related, dual coil is great. If you happen to have a pair of signals that always go in opposite directions already, the single coil is great. There was a trick with a SPST switch and a capacitor that made a single coil latching work, but I can't remember exactly what it was now. It's in the archive.

Both forms of signals - that is (a) separate up and down pulses and (b) complementary u/d and d/u signals - exist in different setups. The trick is to pick the relay which matches what you already have, or that you can derive most easily. Both pairs of signals contain the same information.

[Processaurus]

On my last smallbear order I bought, a relay to mess with. (Panasonic TQ2-L-9V ) it took me a couple of hours to figure out that is not a dual coil latching relay thus the the Geo latching relay driver can't be used to drive it. Can anyone point me in the direction of a simple circuit using a momentary switch to drive this.

(Searching the forums brings leads me to this dead link, www.geocities.com/transmogrifox/relay
if anyone give me a copy to look at it I would appreciate it.)

Thanks,
Andrew.

I did that exact same thing!  Looked up the datasheet and everything, but it didn't register that they were single coil.  They don't seem particularly useful... except as a $7 lesson.

[R.G.]

They don't seem particularly useful... except as a $7 lesson.

Man, I wish I could get my lessons for only $7 each!!   

[theused69]

i need those relay driver schematics too, does someone still have a copy of those?

[smallbearelec]

I apologize for the screwup. When I picked those parts to stock, I thought I was getting the ones needed to implement a circuit at GEO.

R. G.: If you will recommend an appropriate dual-coil part, I will order and send to those who suffered because I did not do enough homework.

SD

[Processaurus]

I apologize for the screwup. When I picked those parts to stock, I thought I was getting the ones needed to implement a circuit at GEO.

R. G.: If you will recommend an appropriate dual-coil part, I will order and send to those who suffered because I did not do enough homework.

SD

Thanks very much, Steve!  The dog ate my homework on that count as well.  I'm currently using the orange NEC 5v latching relay, the EA2-5TNJ, from Mouser, based on RG's previous recommendation here on the series, and because they're $2.50.  NEC has a special 9v part but it seems harder to find and more expensive.  This one works wonderfully in the Geo circuit using a 130 ohm resistor in series with each coil, reliably down to a supply of 6 volts.

i need those relay driver schematics too, does someone still have a copy of those?

I couldn't find Transmogrifox's schematic anywhere, but the Geo one works, there's some discussion of it here:
http://www.diystompboxes.com/smfforum/index.php?topic=82010.0

[smallbearelec]

I just saw this. Will order the dual-coil item. If you ordered the single-coil part, e-mail me and I will replace.

SD

[Beo]

Does anyone have a copy of Transmogrifox's single coil latching relay circuit that they can post? Looks like his geocities page is gone, and he hasn't been active on the forum in a year.

Thanks,
Travis

[bluelagoon]

The single and double coil relays are both useful. Which is most useful at the moment depends on what you already have. If what you have is a pair of signals that pulse for A or B, but are not otherwise related, dual coil is great. If you happen to have a pair of signals that always go in opposite directions already, the single coil is great. There was a trick with a SPST switch and a capacitor that made a single coil latching work, but I can't remember exactly what it was now. It's in the archive.

Both forms of signals - that is (a) separate up and down pulses and (b) complementary u/d and d/u signals - exist in different setups. The trick is to pick the relay which matches what you already have, or that you can derive most easily. Both pairs of signals contain the same information.

Thanks RG as always, for some great electronics guidance. There is a good article at the following web link to explain a low power relay switching scheme using a single coil latching relay such as the Panasonic TQ2-L-5V where it uses a capacitor charge , discharge to switch the single coil relay
https://www.freestompboxes.org/viewtopic.php?t=31684&start=200