relay switching with 5v taps from power transformer

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1000uf
Posts: 10
Joined: Fri May 04, 2012 2:56 am

relay switching with 5v taps from power transformer

Post by 1000uf »

hi i am new to this forum and i am glad i found it. i am trying to build a dumble clone and have tried to use my 5v taps from my heybore bassman transformer so I don't have to get a separate transformer. can i plug them straight into the relays?
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M Fowler
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Location: Walcott ND

Re: relay switching with 5v taps from power transformer

Post by M Fowler »

No you need to build the regulator such as Ceriatone uses to power your relays.
1000uf
Posts: 10
Joined: Fri May 04, 2012 2:56 am

Re: relay switching with 5v taps from power transformer

Post by 1000uf »

wow that was fast! thank you :D
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ToneMerc
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Location: East Coast

Re: relay switching with 5v taps from power transformer

Post by ToneMerc »

You can actually go the sans regulator route using the taps by incorporating a either a bridge suppply or doubler circuit. I built a couple of Brownnote Amps using just the 5V taps and bridge PS using low current 5V relays.

TM
Smitty
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Rectifier Heater Tap Powering Relays

Post by Smitty »

I've had some success with this. I'm using a voltage doubler with 1N4007s and 470uF caps and can power four 5V relays. I'm using a 7806 and running the LEDs in series.

With a regulator you open up more options as to where you can ground things. I'm able to use a three conductor swichcraft 1/4" jack that grounds to the chassis right next to the input jack on my Fender-style chassis. If there's going to be problems this is where it would be. I can hear no hum nor see it on the scope.

I like this because I can use a 1/4" stereo jack and the Antique Electronic Supply two button footswitch with LEDs. Just need to rejigger the unit...see the Brown Note forum or here...I forget.

I bypass the relay coils with a 1n4007 and a 47uF 16v cap to cut down the pop. I'm still experimenting with cap size...

I'm trying a bridge rectifier with low forward voltage schottkys, more capacitance and a low drop out regulator to see how much current that tap can supply. Here are the parts I found after scowering mouser:

Panasonic Aluminum Electrolytic Capacitors - Leaded 4700uF 16V
Mouser Part #: 667-ECA-1CM472
Manufacturer Part #: ECA-1CM472

Vishay Schottky Diode40 Volt 1.0 Amp 35 Amp
Mouser Part #: 625-SB140A-E3
Manufacturer Part #: SB140A-E3/54

STMicroelectronics Very Low Drop 5V Regulator 0.45V 50uA 500mA
Mouser Part #: 511-LF50CVDG
Manufacturer Part #: LF50CV-DG

The relay I use was discovered in a post on this site. Thanks to whomever posted it.

Omron 2A DPDT 5VDC 360mW Radio Frequency Relay
Mouser Part #: 653-G5V-2-H-DC5
Manufacturer Part #: G5V-2-H-DC5

You don't need the full 5V to switch these relays. If you're sure you're going to have 120 volts at the wall, no worries. I need to test this with a variac down to 110V. Might need some really low voltage LEDs to make this whole deal work below 110V.

I'm going to increase the voltage of the 5V regulator by putting a diode on the ground leg. You can't ground the body tab on the relay when you do this because it now has voltage on it. Going to leave it floating for now. By increasing the output voltage of the 5V regulator I can still have the LED in series with the relay ala Brown Note.

Hope this helps
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