HeathKit IG-1272

There's one on eBay. Perhaps the seller has the manual.

Bob

Why don't you test the other two and see what voltage and current lightes them up brightly.

Then you know the ratings you want.

Incandescent ( tungsten) lamps with of the same rating behave very similarly.

..... Phil

wrote in news:sKadnbctJKIsQW_anZ2dnUVZ snipped-for-privacy@comcast.com:

I'm looking at my manual and...nothing. Just identified as a tungsten filament lamp and a Heathkit part number. No voltages given on the schematic or in the circuit description.

Try measuring the resistance of one of the surviving lamps. Since these barely glow, if at all, current has to be very low and I'd make a wild guess that they're rated for a fairly low voltage.

The Mouser catalog lists some potential (sorry!) candidates by Chicago Miniature:

--Damon

"Damon Hill"

Best buy half a dozen and match them for dull red brightness when in the unit.

...... Phil

Thanks all. That's what I did. They seem to be 12V @ 40 mA.

With some luck you might find spare bulbs for Christmas light strings that match or can be combined. But don't just pluck them out of the strings in your garage or the missus will be rather grumpy towards the end of the year ("Ron, I can't believe you did this!") ...

Nice thing about those is that you can carefully straighten the leads, slip off the plastic piece and then solder them in.

Hi Group Whew! I found them here:

RonL

Thanks for the link, Ron, bookmarked it right away. Lightbulbs are also excellent devices to make RF noise sources with.