Vanagon EuroVan
Previous messageNext messagePrevious in topicNext in topicPrevious by same authorNext by same authorPrevious page (January 2017, week 1)Back to main VANAGON pageJoin or leave VANAGON (or change settings)ReplyPost a new messageSearchProportional fontNon-proportional font
Date:         Fri, 6 Jan 2017 20:40:48 -0500
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: Dang driver lowbeam and front driver turnsignal
Comments: To: Jim Felder <jim.felder@gmail.com>
In-Reply-To:  <CAFnDXk0wHWTNo3ZardvL2ot7K-Ht0REECJw1n6T5x4aa_djL9w@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8

Compared to old RS meters the "real" ones had much better construction as well as available leather and roll-top cases; but also better-balanced and more robust meter movements, and better accuracy. Some had "taut-band" meter movements that are particularly robust, with no danger of cracked jewels. Better balance means you can use them upright without the reading changing much (all analog multimeters are specified to be used on their backs for stated accuracy).

It's difficult to make a sensitive (high-impedance) meter that also responds quickly, and the larger the meter face the more difficult this is. This is one of the things that drove the VTVM (vacuum tube voltmeter) and later transistorized meters (which are what established the 10-megohm input spec I mentioned in my first post). The little pocket meters respond quicker, but only a very few expensive ones have higher than 2,000 ohms per volt sensitivity, which makes them unsuitable for many low-voltage electronic purposes.

On Fri, Jan 6, 2017 at 8:07 PM, Jim Felder <jim.felder@gmail.com> wrote:

> I followed Stuart's link and bought one of the compact Radio Shack meters. > It arrived today. I really like it for its practicality. You can fold it up > and not worry about the cords getting snagged and messed up, which is what > happens to most I carry around in a toolbox. It's great for what it is. I > also have Harbor Freight digital and old-school d'arsenval meters, they are > all useful for something. If I had to pick one to keep, it would be a top > of the line Harbor Freight digital or maybe a big 1980s Radio Shack meter, > hard to say. Sometimes it is better to watch a meter fluctuate than to read > a bunch of numbers. > > Anyway, they all know a lot more about electronics than I do. > > Jim > > On Fri, Jan 6, 2017 at 6:42 PM Stuart MacMillan <stuartmacm@gmail.com> > wrote: > > > Good ole Harbor Freight! Some for $4.99, which one do you like? > > http://www.harborfreight.com/catalogsearch/result?q=multimeter > > > > > > > > Stuart > > > > > > > > From: dbeierl@gmail.com [mailto:dbeierl@gmail.com] On Behalf Of David > > Beierl > > Sent: Friday, January 06, 2017 4:24 PM > > To: Stuart MacMillan > > Cc: vanagonlist a > > Subject: Re: Dang driver lowbeam and front driver turnsignal > > > > > > > > Stuart, Harbor Freight has $6 (sometimes free) meters that are perfectly > > adequate for almost all van electrical stuff (better than the RS folding > > one in some ways) and easier to find/use for one fifth the price. > > > > What you need in a van digital multimeter are: > > > > Banana jacks so you can use different test leads or adapters. > > > > Power switch that is not a pushbutton that could get turned on in your > > toolbox. > > > > Manual ranges -- auto-ranging is nice, but if you can't turn it off it > can > > drive you nuts in some circumstances. Much better to not have it than > have > > one that can't be turned off (most auto-ranging *can* be turned off). > > > > > > > > Accuracy -- the cheapest digital meter is more accurate than all but > > extremely expensive analog meters, and accuracy is specified in terms of > > the reading rather than the meter full scale. It will be good enough, > > sight unseen, until you are advanced enough to work out the ramifications > > yourself. > > > > > > > > High impedance -- the standard input impedance for electronic voltmeters > > is ten megohms, which is excellent. The lowest I've seen on a digital > > multimeter is one megohm, which is still plenty for any normal van > > purposes. Cheap analog meters have an impedance of 2,000 ohms for every > > volt on the scale, so a ten-volt scale would have 20,000 ohms. Sounds > like > > a lot, but it will drag your oxygen sensor practically to ground. Huge > win > > for digital in this case. > > > > > > DC Volts -- 20, 2, 200 mV (fancier meters with more "counts" may read up > > to 3999 or 4999 on a range instead of 1999). > > > > > > > > DC Amps -- Ten or twenty amps and a milliamp range of some sort. Note > > that the high-amp range on cheap meters is usually un-fused, so if you > try > > to read volts with the leads connected for amps you will smoke the meter > > shunt and maybe melt the meter case. OTOH the fuses on my fancy Fluke > > meter cost more (each) than the entire HF meter... > > > > > > > > Ohms -- 200 ohms to at least two megohms ranges. You won't actually use > > these often, as you'll mostly be concerned with resistances that are too > > small to measure accurately (or at all) by this technique. Instead > you'll > > be using the 200 mV scale on live circuits to get voltage drops directly, > > which is the number that matters in any case. In effect you are turning > > the van and meter together into an extremely fancy ohmmeter that can > > measure milliohms or even microohms. > > > > > > > > Diode Test -- Like ohms, but shows voltage across a semiconductor that's > > conducting. Modern digital ohmmeters use too low a voltage to turn on a > > semiconductor junction, so they have a special function that will. It's > > nice if this function has enough voltage to turn on blue/white LEDs -- > some > > do, some don't. Pretty much all of them will work with red/yellow/green > > LEDs, and all will work with germanium or silicon diodes. > > > > Your $6/free HF meter does all this. For an extra buck or two you can > get > > one with a light. > > > > Things that are nice: > > > > > > > > Continuity buzzer -- nice, but can bite you since they usually beep > > somewhere between 50 and 150 ohms. That's ok if you're looking at a > > circuit with an incandescent light installed in it, but not for wires > > connected together, switches and so forth. But if you ever get a chance > at > > an old Hickok meter with ?Vari-Trak? (audio beeper that changes pitch > with > > the meter reading) grab it. It's a huge pity they went out of business > and > > nobody has picked up this idea. > > > > > > > > Bar graph display -- digital meters typically take 2-4 readings per > > second, and average the reading over the measuring period which will be > > roughly one-third of the cycle time. For rapidly changing readings (like > > the oxygen sensor on the van) this can lead to readings that appear > > random. Slightly fancier meters often have a secondary bar graph display > > that isn't precise but responds much more quickly than the main display. > > > > Illumination -- can be very handy. If I had to pick between continuity > > buzzer and light I'd probably pick the light. > > > > > > > > Display hold -- lets you make a measurement and capture the reading to > > look at in better conditions. > > > > > > > > Min/Max -- captures the highest and lowest values of a reading. Handy > for > > example when measuring voltage drop during cranking. > > > > > > > > Frequency/duty cycle -- good for PWM (pulse width modulated) signals like > > the 2.1l Idle Control Unit output, LED dimmers and such. > > > > DC+AC -- digital meters on DC ranges typically ignore AC. This function > > gives a separate reading for any AC component of a DC signal, like ripple > > and hash on the alternator output. Probably only on quite fancy meters. > > > > Type K thermocouple input for temperature. Even nicer if you can switch > > the reading for F or C. > > > > > > > > Auto-timeout on light and meter power -- can save your battery. Can also > > be a nuisance, so even nicer if you can shut if off. > > > > > > > > Yours, > > > > David > > > > > > > > > > > > On Sun, Jan 1, 2017 at 11:19 PM, Stuart MacMillan <stuartmacm@gmail.com> > > wrote: > > > > No, you are not being obnoxious, basic electrical troubleshooting > requires > > one. At least get of one these, I give them away to my friends and > family: > > https://www.radioshack.com/products/radioshack-22-range- > pocket-digital-multimeter > > I now have a Fluke meter, but I still have the Radio Shack pocket VM I > > bought at least 30 years ago in my Vanagon on-board toolkit. > > > > Stuart > > > > > > -----Original Message----- > > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf > > Of Dennis Haynes > > Sent: Sunday, January 01, 2017 7:43 PM > > To: vanagon@GERRY.VANAGON.COM > > Subject: Re: Dang driver lowbeam and front driver turnsignal > > > > I’ll ask for forgiveness in advance for sounding obnoxious. Besides > > changing parts did you consider using a meter? Each headlight high and > low > > bam does have its own fuse, yes 4 fuses for the lights. They are after > the > > switches in the headlight circuit. The turn signal sounds like a bad > > ground, probably at the socket itself. The 4 way flasher is not an > > independent circuit. The flasher will not flash unless it sees enough > > current being drawn for two bulbs. High resistance in the working or a > bad > > bulb will prevent the flasher from working. This acts as an indicator > of a > > turn signal being out. The 4 ways connect 4 lamps so if one or two were > out > > it will still flash. Headlight grounds are also a common problem. There > are > > grounding clusters above the fuse box. It is common for the quick slide > > connecters to both corrode and also break just from heat and age. As the > > headlights are higher current items new ground connections near the > > headlamps are a good idea. > > > > Dennis > > > > > > > > -----Original Message----- > > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf > > Of C B > > Sent: Sunday, January 1, 2017 7:48 PM > > To: vanagon@GERRY.VANAGON.COM > > Subject: Dang driver lowbeam and front driver turnsignal > > > > My driver lowbeam won't work at all. > > What didn't help: > > Swapped bulbs. > > Replaced turnsignal ring & stalk. > > Replaced dash headlight switch. > > Traced wires and pulled apart the fuse block and driver's side wiring > > stars connectors. (Should I try the passenger side one?) > > > > In addition, the driver front turnsignal stays on and won't flash whether > > just parking lamps, or either headlight combination is on. > > BUT the driver front flasher works in emergency 4-way flasher mode > > regardless of parking light/headlight configuration. > > I know the 4-way flasher is its own circuit, so where in the > > parking/headlight circuits are likely culprits? > > > > Other than that, Cunegonde finally home and ready for visual restoration. > > It's been a long several years since the engine debacle. > > > > > > CUNEGONDE 1985.5 2,1l WBX 4sp Westfalia > > > > > > >


Back to: Top of message | Previous page | Main VANAGON page

Please note - During the past 17 years of operation, several gigabytes of Vanagon mail messages have been archived. Searching the entire collection will take up to five minutes to complete. Please be patient!


Return to the archives @ gerry.vanagon.com


The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.

Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.