Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: dinkyguitar on June 25, 2020, 05:01:53 pm
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Hi All,
Not sure if this belongs here, but I have a blue jewel, but when the amp is powered on, it shines white.
Anyone have this issue?
I was trying to see if i could get a blue light bulb to make it blue, but haven't found one yet.
I'm using these.
https://www.mojotone.com/amp-parts/PilotLights_1/1-2-Lens-Assembly-Blue-Jewel
After looking at this picture...is it supposed to turn white when it's powered on?
dinky
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go to the hobby store, pick up a small glass of blue paint for models. enamel, not sure urethane will like the heat :icon_biggrin:
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Buy one from Hoffman.
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Normal incandescent lamps make very little blue. Mostly red. Even with a blue filter they look white.
Convert to blue LED. It can be fed 6.3VAC through a 330 Ohm series resistor, but will flicker if you move your head fast. Two blue LEDs anti-parallel on one 330r will flicker less, and less reverse-stress on the LED. There are cleverer plans but it's only a pilot light.
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https://www.ebay.com/c/1031492460?iid=252495546075 (https://www.ebay.com/c/1031492460?iid=252495546075)
--pete
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Hi All,
Not sure if this belongs here, but I have a blue jewel, but when the amp is powered on, it shines white.
Anyone have this issue?
I was trying to see if i could get a blue light bulb to make it blue, but haven't found one yet.
I'm using these.
https://www.mojotone.com/amp-parts/PilotLights_1/1-2-Lens-Assembly-Blue-Jewel
After looking at this picture...is it supposed to turn white when it's powered on?
dinky
On the link one picture show you it come white when power ON
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https://www.ebay.com/c/1031492460?iid=252495546075 (https://www.ebay.com/c/1031492460?iid=252495546075)
--pete
Have you tried these?
@Latole
I did see that pic you are referring to....which is why I'm curious if it's supposed to be like that....
But if you're getting a colored jewel, wouldn't you want it to stay that color when powered on?
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But if you're getting a colored jewel, wouldn't you want it to stay that color when powered on?
Not realy, IMO color of jewel is not dark enough to stay blue
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Id say Pete's idea of a blue LED inside a blue jewel is worth a try.
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Id say Pete's idea of a blue LED inside a blue jewel is worth a try.
You are right.
We don't know how many Lumens this LED. With this led, amp pilot light may not be very bright in daylight
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Does this give you any ideas?
https://www.bulbtown.com/44B_Blue_Miniature_Bulb_Ba9S_Base_p/44b.htm
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Does this give you any ideas?
https://www.bulbtown.com/44B_Blue_Miniature_Bulb_Ba9S_Base_p/44b.htm
Great !
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https://www.ebay.com/c/1031492460?iid=252495546075 (https://www.ebay.com/c/1031492460?iid=252495546075)
--pete
Have you tried these?
yes. they work fine. i used the dialight brand in red, they were more expensive and now not readily available. LED lamps do last longer than an incandescent lamp.
the seller i linked to is reputable - i have purchased from them in the past.
--pete
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Thanks everyone.....
I like the idea of the LED as well as the colored blue....might try both.
dinky
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The LEDs work great. I've used them exclusively now for the past few years in various forms.
Achieving a rich blue color, however, is not so easy. I have used Hoffman's blue jewel with several different blue LEDs, and they work fine as pilot lights, just not a rich blue.
Using a hard wired LED is simple -- you just have to put a current/voltage limiting resistor in series. This should be in the range of 180-200k @ 20mA, ie a 1/4 watt resistor is fine. You can buy these pre-made on eBay (like everything else, it seems) very inexpensively.
If you have a Fender lamp socket installed, there are pre-made LEDs (with the voltage limiter inside) that fit the sockets. There are several vendors that are selling these -- frankly they are so cheap that you can't go wrong. I've had vendors ship from China, Hong Kong and the US. US shipping is the fastest, but they all work.
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> range of 180-200k @ 20mA
Not "k". Just little Ohms.
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Original # 47, 6.3 volts incandescent bulb are cheap. I'll buy blue paint in hobby shop ( very very small can ) tp pint the bulb.
Or blue colored cover for your bulb ;
Cover:
https://www.bulbtown.com/Blue_Colored_Bulb_Cover_For_T3_1_4_Bulbs_p/39-12-5a.htm
Bulb
https://www.bulbtown.com/47_Miniature_Bulb_Ba9S_Base_p/b47.htm