Express impedance switch Help (Easy I think)

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yalesmith
Posts: 218
Joined: Wed Aug 18, 2010 5:55 pm
Location: Orange County NY

Express impedance switch Help (Easy I think)

Post by yalesmith »

I am trying to figure the wiring on my current buil, and i do suspect it is the cause of my low/no volume issue. I get how the jumpers work but i have 2 questions:

What are the 2 outer lugs on the impudence switch?

Where do you solder the output wire coming from the Jack
Picker
Posts: 98
Joined: Wed Oct 17, 2007 9:30 pm

Re: Express impedance switch Help (Easy I think)

Post by Picker »

I'm not sure which impedance selector you are using, but there is some info on the first two pages of my thread here

https://tubeamparchive.com/viewtopic.ph ... highlight=

If you are using one like mine, I'm guessing that by the "Outer two" you mean the two that are in their own row. They get jumpered to each other and then go to the output jack.
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selloutrr
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Location: Southern California

Re: Express impedance switch Help (Easy I think)

Post by selloutrr »

you can always use continuity to test thru a switch and draw out a diagram.

do you have a make and model of the switch you are using? have you tried to locate a data sheet? those usually will answer most questions.
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Gibsonman63
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Location: Texas

Re: Express impedance switch Help (Easy I think)

Post by Gibsonman63 »

On the first build, I ordered the selector from the BOM. On my second, I got it from rj with the rest of my parts. The one from the BOM was a real pain to wire. The one I got from rj has 4 pretty good size lugs and it was very simple to figure out with a meter and very easy to solder.
yalesmith
Posts: 218
Joined: Wed Aug 18, 2010 5:55 pm
Location: Orange County NY

Re: Express impedance switch Help (Easy I think)

Post by yalesmith »

It is a Electroswitch C4D0304N-A


Thanks!
Picker
Posts: 98
Joined: Wed Oct 17, 2007 9:30 pm

Re: Express impedance switch Help (Easy I think)

Post by Picker »

I think that is the same one I had. It difffered from the Build Guide in that there were 3 sections insted of the four groups mentioned in the guide.

On the top of the selector switch there is a pin that you can move to set the number of stops on the switch. Set Pin to liimit the number of positions for the Selector switch to 3. (I think you put it in the fouth hole to stop it from going any further.

Next, check the continuity using your DMM beween the top and bottom lugs. If I remember correctly there are three sets of four pins (plus the one above each group of four in a separate row one for output of of each group. Double check using your DMM, but I think 1, 5, and 9 are one position on the switch and 2,6 and 10 are the middle position, and 3, 7, 11 are the third position. So you will check for continuity from the top lug to each of the four pins below it. Each setting on the switch will open the connection between one of the Pins.

You are only using 2 of the three groups. Wire a jumper from each pin to its corresponding pin in the other group of 4 you will be using (ie. Pin1, to Pin 5 ..... Pin 2 to pin 6.... Pin 3 to pin 7). You will also be attaching the leads from the Output Transformer to PIN 1, PIN, 2 and PIN 3, corresponding to the 4, 8 or 16 ohm rating.

The upper lugs get wired to eachother and to the output jack.

I'm doing this from memory, but I think that is correct. Double check the layout to be sure and make sure you check with the meter.

Hope this helps :idea:
Picker
Posts: 98
Joined: Wed Oct 17, 2007 9:30 pm

Re: Express impedance switch Help (Easy I think)

Post by Picker »

Here's a picture of mine wired in if that helps.

[img:799:531]http://i54.photobucket.com/albums/g94/r ... C_0887.jpg[/img]
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