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New Member
Hi Guys,

I'm new to this forum, but I'm hoping that someone may be able to give me some assistance.

I have recently purchased three (3) of the Circuitron AW-1 Circuits from Walthers, and have managed to destroy every one, either due to short circuits, bad wiring, or clumsiness, I'm not sure.

True, I have been asking them to do a little bit more than just intermittently flash two 1.5v minilite globes, but I had an old unit running this same circuit for over ten years, without problem, until it simply died of old age.

Has anyone else had any problems with these "newer" units?

And, more importantly, does anyone know where one would access spare parts for them? (They are getting a little expensive at about AU$35-00 each)

The IC is probably the main culprit, and I cannot seem to source one of them, but the diodes, transistors and resistors are all common items.

Has anyone ever attempted to repair one of these boards?

After spending weeks and weeks waiting for these things to arrive here in Australia from USA, I feel like a man holding a thousand bucks worth of unsigned cheques.

Please, can anyone help out an old bloke?



Sorry Anubis, I don't use that type. I use the GRS "Ultimate Arc Welder" that is triggered by the modulated signal of an AM radio. Pricy, but VERY Real! You may want to consider one if you can't solve your problem.


New Member
Circuitron AW-1

Hey, thanks Rex,

I have taken your advice and ordered one of the GRS 'Ultimate Welder' Circuits from Walthers, but I don't understand how the thing is triggered by an AM radio signal. Could you possibly explain it to me?

It will be at least a month before it arrives from US, and in the meantime, I have repaired a couple of my previously inoperable AW-1 circuits.

I managed to locate a supply for the output transistors (here in Australia) and have replaced them on the respective boards.

So, my little welder has got something to do again.

Many thanks.


Very good! I think you will be pleased with it.
I wish that I had a schematic of their circuit, but I believe they tap off the AM radio signal itself, as an AM signal modulates in amplitude with the frequency of the speech or music. This amplitude variation, controls the output voltage to the lightbulb. The bulb will vary wildly in intensity and randomly as a person's speech intensifies or softens.They recommend tuning the radio to a talk-show type of station because there are more sudden and separate variations in speech than music. The volume control of the radio will control the maximum bright or dim the bulb will get It is very real. You will swear that you are seeing a welder.;) :)

Oh yeah, there is an ear plug speaker that connects to the radio so you can tune in the station. Have fun and let me know later how you like it.

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