Search found 39 matches

by Tparker
Sat Oct 18, 2003 8:36 am
Forum: General Discussion
Topic: Problem with motorhome lighting
Replies: 7
Views: 1764

Re: Problem with motorhome lighting

The transistors are mounted on 2 seperate heat sinks that seem adequate. One transistor did show signs of high heat and its phenloic mounting socket came apart when I removed the transistor. I also noticed that no mica insulating "washers" were used and found no evidence of any heat sink compound (t...
by Tparker
Fri Oct 17, 2003 10:53 am
Forum: General Discussion
Topic: Problem with motorhome lighting
Replies: 7
Views: 1764

Problem with motorhome lighting

Having a problem with a friends motorhome panel lighting. Recently he found that his lighted switches and gauge illumination lights (house 120 volt generator panel, holding tank level, etc.) were not turning off when he turned off his headlight switch. The engine gauge lights do not have this proble...
by Tparker
Fri Jun 13, 2003 3:33 pm
Forum: General Discussion
Topic: Blown Strobe Power Supply
Replies: 3
Views: 956

Re: Blown Strobe Power Supply

Nevermind, not sure what I did but I got it working after opening the case (riveted), removing the mosfets from the case bottom where they were bolted for heatsinking and cleaning and resoldering the one side of the fuse holder. Only thing I can think of is either the fuse holder was shorting to the...
by Tparker
Fri Jun 13, 2003 9:05 am
Forum: General Discussion
Topic: Blown Strobe Power Supply
Replies: 3
Views: 956

Blown Strobe Power Supply

I have acquired a 90 watt, 4 outlet strobe light power supply as used on emergency and construction vehicles. The 15 amp on board automotive type spade fuse has been destroyed and the circuit board around the input side of the fuse holder shows a burn mark but the foil has not lifted. The rest of th...
by Tparker
Wed May 14, 2003 9:14 am
Forum: General Discussion
Topic: Increasing Current of 555 timer
Replies: 5
Views: 1295

Re: Increasing Current of 555 timer

Thanks guys for the help. No problem with distance, all mounted on a small circuit board. This will be used in a automotive application so I will not have the power supply problem and will be used with LED arrays, so should not have the cold filament problem. 5 amps is very worst case and will be mo...
by Tparker
Tue May 13, 2003 4:57 pm
Forum: General Discussion
Topic: Increasing Current of 555 timer
Replies: 5
Views: 1295

Re: Increasing Current of 555 timer

Russ if I understand correctly, I would run 12 volts to the lamp and run the ground of the lamp to the drain of the IRLIZ14G? And no other components are needed such as resistors.
by Tparker
Tue May 13, 2003 10:23 am
Forum: General Discussion
Topic: Increasing Current of 555 timer
Replies: 5
Views: 1295

Increasing Current of 555 timer

I have a 555 running in the astable mode and would like to have it drive a 5 amp 12 volt lighting load. Being a novice can someone suggest a transistor/mosfet circuit to do this. Thanks in advance.
by Tparker
Tue Apr 29, 2003 4:46 pm
Forum: General Discussion
Topic: LED current limiting
Replies: 3
Views: 966

Re: LED current limiting

Thanks for the reply. After looking at the data sheet again, the foward voltage ranges from 2.3-3.5 for the red and amber luxeons. The 4 volt spec was for the other colors. I will look at the 317 T data sheet.
by Tparker
Tue Apr 29, 2003 11:57 am
Forum: General Discussion
Topic: LED current limiting
Replies: 3
Views: 966

LED current limiting

I wish to run 3 Lumiled Luxeon Star Led's (350ma @ 2.5-4.0 volts) in a series string. The source voltage will vary from 11.5-14.5 volts (automotive). Instead of using current limiting resistors, could I use a 3 terminal voltage regulator configured for constant current operation. Could I "set" the c...