Slow pilot light

[bluesguitar]

I have a '66 Twin Reverb. No problems with the sound. In fact, it is my best sounding amp. However, I've noticed that if I haven't turned it on in a couple of weeks there is a significant delay in when I flip the switch and when the pilot light comes on. I'm talking as much as 15 seconds, maybe even longer. My only concern is that the delay time seems to be getting longer. My guess is that it is a filter cap issue, and that the caps need to charge. But, none of my other amps have any delay at all concerning the pilot light. I have all new filter caps in the amp. I put the new caps in as soon as I acquired the amp, so I don't know what it did before I owned it. Any ideas on what may be causing the delay?

[NickC]

The pilot light is on the same run as the 6.3V heaters, fed from a secondary on the PT. I don't see how power supply caps could influence it. Ordinarily the pilot light is first in the string, before the heaters.

Maybe the pilot light bulb is malfunctioning?

http://www.turretboards.com/layouts_sch ... layout.gif

[wyatt]

Put in a new bulb.

The little solder blob that forms the contact point at the tip gets compressed over time.

Simplest and most direct solution first. New bulb. Maybe clean the socket.

[bluesguitar]

Thanks for the info and tips. Will look into the pilot light and solder joints as the culprit.

[sliberty]

Do you still have a ground switch? Might be time to remove that death cap.

Pull the power tubes and see if it still happens. If it does, pull the pre amp tubes as well and see if it still happens. If it happens with no tubes, your PT may be in trouble.

[Leo_Gnardo]

What NickC said ^^^. It usually works out to be something simple, corrosion on the lamp "barrel" which you can scrub off with a little wire brush, or that lead "bump" on the end - which you can enlarge with a tiny dab of solder. Also examine the filament carefully. Sometimes it's broken and the ends "magically" find each other and the lamp starts working after a while.

Occasionally the fixture is at fault, and from time to time I find the wires not well-soldered to the fixture lugs.

Think simple. Very rare that pilot lamp problems/solutions are anything but that.

FWIW I use Chicago #755 lamps instead of #47 for replacement. They draw a teeny bit more current but have a much longer rated lifetime. Available from Mouser plus I'm sure some other parts dealers. The #47 lamps you get at Radio Shaft are crap. Lucky to get a month or two out of one.

[Phil_S]

You can buy light bulbs on line and at eBay for dirt cheap. Last year some time I bought a box of 10 #47 bulbs for $3.39 on eBay. As I recall, this was much, much cheaper than anywhere else. For me a box of 10 is a lifetime supply, or pretty close to it.

[Reeltarded]

You need faster electricty.

[Jana]

It takes me 2 cups of coffee before my pilot light comes on.

[jhaas]

You can buy light bulbs on line and at eBay for dirt cheap. Last year some time I bought a box of 10 #47 bulbs for $3.39 on eBay. As I recall, this was much, much cheaper than anywhere else. For me a box of 10 is a lifetime supply, or pretty close to it.

$3.00 for 10 at AES: http://www.tubesandmore.com/products/P-47

[Firestorm]

Might be the power switch itself.

[Phil_S]

You can buy light bulbs on line and at eBay for dirt cheap. Last year some time I bought a box of 10 #47 bulbs for $3.39 on eBay. As I recall, this was much, much cheaper than anywhere else. For me a box of 10 is a lifetime supply, or pretty close to it.

$3.00 for 10 at AES: http://www.tubesandmore.com/products/P-47

Careful now...mine included shipping!

[gingertube]

As stated above - the lamp is on the same supply as the heaters.

Either corroded contact in the pilot light socket or the globe not screwed in securely so it needs to warm up and expand to make the contact.

Try all of above:
- make sure globe is screwed into its socket securely
- clean globe socket contacts (spray contact cleaner)
- replace the globe

Cheers,
Ian

[BIG Dave]

Measure the voltage on the connections on the back of the pilot lamp socket using your voltmeter. Does it measure 6.3 volts? If so, the transformer is fine. Either the bulb is going bad or there's corrosion in the socket.