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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: zubzub on March 18, 2010, 05:08:16 AM

Title: Old School Electrical Question.
Post by: zubzub on March 18, 2010, 05:08:16 AM
As i work on my gages Which seem to work this bit is a little confusing.  There is a resistor? on the + supply side of the temp and oil pressure gages. Resistance is between 25-27 ohms

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi392.photobucket.com%2Falbums%2Fpp3%2Fzubzub_photos%2Fprevost%2520scrap%2520and%25204104%2520interior%2FIMG_0223.jpg&hash=446b1886ab8a198d9c2b5fb39862149f7d5f2407)  the black rubber washer is stabilizing a brass rod with some kind of resistor it,  Are these the diodes I have heard about that need reversing when the vehicle is changed to neg earth?  Or are they just resistors that calibrate voltage going to  the gages? 
Title: Re: Old School Electrical Question.
Post by: belfert on March 18, 2010, 05:28:41 AM
I don't know what voltage a 4104 is, but if it is 24 volts those resistors are probably to bring the voltage down.  My 24 volt gauges all have resistors on them (except the voltage gauge) and my assumption they are to lower the voltage.  The resistors on mine look like an add-on.
Title: Re: Old School Electrical Question.
Post by: wal1809 on March 18, 2010, 05:33:57 AM
I don't know but your killing me with the out of focus pics :o
Title: Re: Old School Electrical Question.
Post by: zubzub on March 18, 2010, 05:58:10 AM
Good point about the pics, I'm usually going pretty fast when I work, don't even check the pics really.  It's better than before when I would bring a camera and never even take a single pic.
Title: Re: Old School Electrical Question.
Post by: JackConrad on March 18, 2010, 06:07:47 AM
Try holding the camera a little further from the subject and then use the zoom to get a "close-up".  I have found that, at least with my cameras, this sometimes helps get a sharper photo.  Jack
Title: Re: Old School Electrical Question.
Post by: HighTechRedneck on March 18, 2010, 06:47:48 AM
Some digital cameras have a close-up (or "macro") mode on the selector dial that is specifically for photos closer than 18"
Title: Re: Old School Electrical Question.
Post by: luvrbus on March 18, 2010, 06:57:22 AM
Pat,I got to ask the question too much temptation for me how in the world do you work on the electrical wearing the hand panties I see in every photo 

good luck
Title: Re: Old School Electrical Question.
Post by: scanzel on March 18, 2010, 07:10:15 AM
These are probably resistors to bring the voltage down to 12 volts for the guages on a 24 volt system. When I have my military dodge power wagon years ago they had one large resistor under the dash to drop down 24v to 12v for the dash guages.
Title: Re: Old School Electrical Question.
Post by: zubzub on March 18, 2010, 07:12:34 AM
Hand Panties! Well I never! ;D  Actually i have been wearing gloves of one type or another for years. Started with latex, but they fall apart in seconds, then went to Nytril equivilant, they lasted longer, but HF is the only place I know where I can get the size, price and thickness I like (thicker than latex but still thin).  Now I am a convert to a light cotton glove with Nytril fingers.  these will last all week sometimes, if you get the right size they give great feel, and if you buy at the dollar store, $1 a pair.  I was working all junction wiring etc yesterday, had to take off my gloves twice, once to get a screw on to a buried relay post, and the other to eat.
The other advantage of  gloves is your fingers don't get covered with grease, so one could even hypothosize that after an hour or so of work, my gloved hand has more feel than your filthy grimy paw. :D
Title: Re: Old School Electrical Question.
Post by: zubzub on March 18, 2010, 07:13:31 AM
Quote from: scanzel on March 18, 2010, 07:10:15 AM
These are probably resistors to bring the voltage down to 12 volts for the guages on a 24 volt system. When I have my military dodge power wagon years ago they had one large resistor under the dash to drop down 24v to 12v for the dash guages.

Good theory but it's a 12V all the way bus.  It's so old I'm lucky it's not 6 volt.
Title: Re: Old School Electrical Question.
Post by: wal1809 on March 18, 2010, 07:16:09 AM
Quote from: luvrbus on March 18, 2010, 06:57:22 AM
Pat,I got to ask the question too much temptation for me how in the world do you work on the electrical wearing the hand panties I see in every photo 

good luck

;D :o  Hand panties!!!!!
Title: Re: Old School Electrical Question.
Post by: Eagle on March 18, 2010, 09:07:35 AM
Quote from: luvrbus on March 18, 2010, 06:57:22 AM
Pat,I got to ask the question too much temptation for me how in the world do you work on the electrical wearing the hand panties I see in every photo 

good luck

Clifford if you ever walked into an automobile factory you would see that everyone on the assembly lines wears some type of cotton gloves.
Title: Re: Old School Electrical Question.
Post by: luvrbus on March 18, 2010, 09:11:02 AM
I know JC I just can't work in gloves and Pat is dealing with very small parts, did the gauge fix your problem


good luck
Title: Re: Old School Electrical Question.
Post by: Chopper Scott on March 18, 2010, 10:49:22 AM
Hand panties, 6 volt bus!! :D This is turning into a pretty good thread! :D