Latching Switch Assemblies

[bishka]

Hello All,
I am in the design stage of a (subminiature)valve/transistor sub mixer.
I haven't done any electronics for about nine years and have not done anything with valves for about thirty or more!! So I am some-what out of touch with what is and is not available.

I wanted a 6 pole 3way make before brake switch.

I can't seem to find what Maplins use to call Interlocking Push-button Switches and Assembly (like the push switches you use to get on HiFi's in the 70's/80's). Are these still available? Or does anyone know of a 6pole 3way switch, it does not need to be a bank of push switches, rotary would be fine.
I did wonder about using small relays but a make before brake relay??????
Any ideas would be gratefully received.

regards Bishka

[M Gregg]

Originally Posted by bishka

I wanted a 6 pole 3way make before brake switch.

I can't seem to find what Maplins use to call Interlocking Push-button Switches and Assembly (like the push switches you use to get on HiFi's in the 70's/80's). Are these still available? Or does anyone know of a 6pole 3way switch, it does not need to be a bank of push switches, rotary would be fine.
I did wonder about using small relays but a make before brake relay??????
Any ideas would be gratefully received.

regards Bishka

I know what you mean it seem these days that the electronics hobby is not so well supported as it used to be!

Maplin do a rotary switch, however not make before break and only 2 pole 6 way!

Why do you need make before break?

You could do it with relays and use a discharge cap across each coil. This would slow the relay down on power off.

The other way is to switch each relay with a darlington/super alfa pair using a capacitor from + to the base of the first transistor when you power off the leakage of the cap will give you a time constant for each relay! you could pulse a decade counter and connect the darlington inputs to this. You may have to de-bounce the switch. Or use the output from the rotary SW. It is a lot of work to achieve the result.

http://www.tep.org.uk/PDF/Control%20...OS%204017).pdf

Regards

M. Gregg

[M Gregg]

Another link!

Make before break seems to be called shorting! Type 6 might be interesting.

Elma Electronic Americas English Products: Rotary Switches, Selector Switches, Selector Switch Type 01, Selector Switch Type 04, Selector Switch Type 06, Selector Switch Type 07R, Selector Switch Type 08, Rotary Switches (FEL)

[bishka]

Sorry I should have explained myself a bit better, the switches are/were for switch between frequancy bands in the filter section, hence they needed to be make before brake to illiminate any thuds from partly charged capacitors.

As I'm 'new' here my messages are vetted before they get posted, which is fair enough, but during that time I've been looking around a bit more on the net and come to the conclusion that I would be better off going down a different road. Anyway thanks for the sugestions, I have just so lost touch over the years, and I have forgotten so much, it's like having to start all over again!!!

Thanks again.
Regards Bishka

[M Gregg]

Hope you achieve what you are trying to do!

Regards
M. Gregg

[AuroraB]

Unfortunately there's a lot of things that used to be easy to find that's now next to impossible to buy in small quantities. That's just the way things have evolved in tlhe electronic bussiness.

However - the proposed Elma switch could be a solution. And there was also Lorlin switches....
Most of the major vendors, like RS, Farnell and even US Digikey sells small order on card payment....

[Wavebourn]

Originally Posted by bishka

I did wonder about using small relays but a make before brake relay??????

Yes!
They break with longer delay than make. It is one option.

Another option is to go on ePay and search for a rotary switch. I bought some nice ceramic military switches from some guy from Estonia.

[bishka]

Thanks for the reply, but I checked ebay, Rapid Electronics, Maplins and Radio Spares before posting here. I was hoping some one might say 'Try so-and-so!'

I would not even call myself a jack of all trades...more like a bodge-it of all trades (who sometimes gets lucky). The switches were part of a work around for my ignorance, I wanted to be able to swich in and out bass, treble and mid range controls in a sub mixer for my home studio, but I also wanted to have some adjustment of the turn-over frequencies. Largely because when I'm mixing I find real knobs easier to use than software knobs (My music studio is all software now that I have sold off all my hardware synths).

My second option was to use an L/C T filter and a discrete opamp for the mid range but, I tried it once before and it tended to ring, but that was with a home wound 11mH coil, so maybe a shop bought coil would fair better. If it doesn't I think I'll go for option 3...Not bother!!

Thinking about it now as I type this, I could always make the EQ section an add-on, that way I can get on with the bit I know and leave the bit I don't know 'til later, and, when/if I do make the EQ section, if I muck it up it won't affect anything else!!!

Ha, think I'm sorted! Thank-you, you stopped me thinking in circles.

Regards Bishka

[mashaffer]

Sometimes it seems odd the things that are hard to find. Been looking for log taper 100K slide pots (Faders) with very little luck.

[bishka]

100K log pots:-

Cricklewood Electronics - CCTV. CCTV Equipment. CCTV Systems. Digital CCTV Cameras

You will have to email them with your order, you can not do it through thier website.

Hope this helps.

regards Bishka