channel switching help please

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Curranproducer
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channel switching help please

Post by Curranproducer »

Here is a pic of the schematic I am doing for a two channel amp. When I hard wire the each channel form the input buffer tube to the fx loop all is good each channel is wonderful! when I try to implement the relay switch(hoffamn relay board) I get a fail. the distortion channel stays on and no clean channel what so ever. I have tried a few different wiring attempts with the relay and have gotten channel switching to happen but with OBVIOUS channel bleed happening between the two channels. please help me understand where I should "break" the relay into the circuit.
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Curranproducer
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Re: channel switching help please

Post by Curranproducer »

Sorry aboot that with the pic, I realized I did not upload it properly! DERP!
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xtian
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Re: channel switching help please

Post by xtian »

When you’ve got the relays wired in, test the circuit with your multimeter, testing continuity between points on the schematic. You should be able to find either an error in your wiring, or a malfunction with the relay(s), right?
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Curranproducer
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Re: channel switching help please

Post by Curranproducer »

I will begin the testing of the continuity. BUT right out of the gate is my wiring looking like the correct kind of layout for a good switch set up?
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Curranproducer
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Re: channel switching help please

Post by Curranproducer »

well the darn relay is NOT switching at all, I have now rewired this goober so many times my head is SPINNING. so I am posting pix of the wiring setup, for a smarter mind than mine to illuminate my failure so I may learn more betterly! HA

the red wire is feeding 5vDC to the relay board Pin 16.
pin 1 is going to the TIP of the FTSW jack.
pin 13 is coming off of the coupling cap of V1.
Pin 4 is feeding into the FX loop input.
Pin 11 is coming from the gain control of the distortion channel and the 470K/500pf, 470K/1000pf switch set up.
Pin 6 is feeding distortion volume control.
Pin 8 is coming from the EQ input of the clean channel.
Pin 9 is feeding the clean volume control.

the ground wire from the power board is connected to the non switching ground of the ftsw jack
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Last edited by Curranproducer on Sat Jan 27, 2018 7:25 pm, edited 2 times in total.
Curran

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xtian
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Re: channel switching help please

Post by xtian »

Schematic look ok, in terms of switching arrangement.
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Re: channel switching help please

Post by xtian »

In the photo of the relay, you've got a red wire attached to pin 16, the negative terminal. Is the red wire your +5v supply? And the blue wire is to ground?
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Curranproducer
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Re: channel switching help please

Post by Curranproducer »

yes, this is correct. I have the relay board wired up like the schematic from Doug Hoffmans page, BUT the +/- on the relay is backwards or "flipped" to the schematic and the diode direction, but i followed the board layout, and the web page wiring plan. I have a video for the relay itself showing a way to test if the relay is switching with a 9v battery and I am not hearing any physical relay clicking when I do the test. SO I think my relay is bad and I may have burned it up pr something, BUT there has been no smoke. NOW if I have had the 5vDC on the wrong pin for the relay, BUT the diode is revered will this burn up the relay? OR do I just flip the diode and the wiring to match the + on the relay?
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Re: channel switching help please

Post by dorrisant »

The diode looks like it is fine with the polarity you have hooked up at the relay board. Yes, it is the opposite polarity of what is specified on the PCB but that should make no difference as long as the diode is reversed as well. If the diode was backwards in relation to the supply voltage polarity you would have a dead short across the diode from your relay B+ to ground, but as it is, it should work.
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