powering relays and leds issue...

[daz]

Hi all,
I built a d'lite awhile back with relays and footswitch but recently wanted to change the footswitch to have leds powered from the amp.
I used this power supply for the relays powered from the heaters:
[img:339:228]http://www.el34world.com/projects/image ... eeburg.gif[/img]

Relays I'm using are omron 5v G6A-234P-ST-US .
The relays worked fine without leds, but when I wire in the leds, the OD and PAB work fine when I switch each on/off individually. But with both switched on sound either cuts out or stays in clean mode.
So the leds are drawing too much current so there's not enough voltage to the relays (thanks for confirming normster).

So what are my options so it will get enough voltage:
1. Norm suggested a 5v voltage regulator. Any circuit schems available?
2. I have single Common Tap, 5 Volts tap, 6.3 Volts tap not being used on the PT.
3. I also have a small 12.6v PT with 6.3v and common taps I could use to just for relays/leds :
Specs:
12.6V CT, 150mA 2VA Centre Tap - Type 2851 Transformer

Specifications:
Primary voltage: 240VAC only +5% 50Hz (I'm in australia)
Secondary Voltage: 12.6V CT @ 150mA
Magnetising current: ~20mA
Total Power rating: 1.9VA
Temp rise above ambient at rated output: ~40°C
Regulation (Typical): ~7.5%
Weight: ~124 grams
Secondary Connection: 200mm flying leads.
Primary Connection: 200mm flying leads

Secondary Voltage Available
Voltage Current
6.3V 150mA
12.6V 150mA

Ideally I'd like to keep the same power supply circuit (if possible) to minimise what's already done.

[LOUDthud]

That 180 ohm between the two 4700uF caps is dropping too much voltage when both relays are on. Reduce that resistor to 47 ohms or so.

[daz]

That 180 ohm between the two 4700uF caps is dropping too much voltage when both relays are on. Reduce that resistor to 47 ohms or so.

Awesome - thanks for that - I'll adjust and report back.

[daz]

Yep 180 ohm was dropping the voltage too far below what was required when both relays were on. 417 ohm did the trick. Ta!

[Fischerman]

daz,
Even though you got it working...here is a thread I started just this past Sunday when I hit a similar problem. Maybe you'll get something out of it.

One thing I learned was not to try to get too much voltage from such a low voltage source (I used the 5vac rectifier filament secondary). When I used an adjustable Vreg (adjustable up to something like 30vdc...with proper supply)...I got 5.5vdc with no relays on but it dropped all the way down to 4.4vdc with both relays on. Then I went to a 6v Vreg and only got 5.3vdc with no relays on but the voltage with both relays on increased to ~4.55vdc. Then I went to a 5v Vreg and got 5vdc with no relays on and 4.65vdc with both on. I should have used a voltage doubler instead of the bridge and then it would probably stay at 5vdc even with both relays on.

I don't know what I'm doing (obv) but you might get something outta that thread.