Bottlehead Forum
Bottlehead Kits => Crack => Topic started by: JSitthi on November 05, 2011, 10:21:14 PM
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Hey Bottleheads,
I'll be receiving my Crack kit this Monday but I'm having a hard time finding a multimeter sufficient for this project. I'm seeing the Fluke brand being thrown around here but I'm not willing to spend that kind of money. What are some cheap alternatives? I currently have this multimeter that I got for free from Harbor Freight, but I don't think it has the correct AC and DC range for this project: http://www.harborfreight.com/7-function-digital-multimeter-90899.html
Any suggestions?
Thanks!
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For $5 you can't go wrong. Although I am a big fan of Harbor Freight if you continue this hobby you will want a better meter some time. Used Flukes can be had for under $100, often in the range of $60-$80. The Fluke will change ranges for you. For instance you set it to DC and it will read a C cell, 1.5V, and the B+ on a Paramount ~470V, no switching ranges.
Edit: See, this is what I use for starting my charcoal grill. I got tired of those awful paraffin and sawdust things taking over 30 minutes to start the fire in my Green Egg. With this I fire it up it throws a 3 foot flame and throw on steaks in 5 minutes:
http://www.harborfreight.com/propane-torch-with-push-button-igniter-91037.html
Can you imagine Tim Allen with one of these?
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You might look at something like: Triplett 1101-B (under $40)
I have one of those $5 ones in my tool box for emergencies and it is not very good.
But, I am comparing this to my main meter, a Fluke 8060A
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For $5 you can't go wrong. Although I am a big fan of Harbor Freight if you continue this hobby you will want a better meter some time. Used Flukes can be had for under $100, often in the range of $60-$80. The Fluke will change ranges for you. For instance you set it to DC and it will read a C cell, 1.5V, and the B+ on a Paramount ~470V.
So are you saying that I could get through the build using this $5 meter? If it's possible, I'll do it. I'm trying to maximize the money I save from building it myself!
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The Harbor Freight meter will give you readings that are fairly accurate. What will give you trouble is when you are on the low end of a range. I advise that you squirt glue in the 10A probe hole to keep you from ever using it as well as never trying to measure milli-amps either. Until you are skilled those can get you in trouble.
When it comes to checkout time you can post anything GREATER than 15% out of spec here in the forum.
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I agree with not wanting spend a lot of money but, as Grainger49 already said, sooner or later you are going need a better device. And if you continue in the hobby you will at some point wish you had one. Another good alternate to fluke to consider are the Agilent line. I picked up a brand new one on sale for $100.00 Model U1233A. It even came with the traceable certificate of calibration.
So far I have found it to be a great low cost aid to my building.
Cheers
Mike
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I've used flukes since 1984. I have replaced the batteries twice, blew a fuse once. I have never even questioned the reading I have gotten. Poster Paully has this one (I think):
http://www.ebay.com/itm/Fluke-15B-Auto-range-Digital-Capacitance-Inductance-multimeter-meter-Test-17B-/220868418663?pt=LH_DefaultDomain_0&hash=item336cc89c67
$55 +shipping is a good price.
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Yes, buy that one. I was looking around for things to suggest. That is a good meter at a good price...John
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Guys, poster JSitthi is building his first project - there's no need to spend as much on the meter as on the kit! The Harbor Freight meter has the DC voltage and resistance ranges needed to do the kit. The only place it falls short is low-voltage AC ranges (doesn't have any below 200v). Those will come in handy eventually if you build more kits, but I'm a big fan of not spending too much on tools until you are sure you'll need them.
I have 4 or 5 meters myself - only one is a really good Fluke; the rest are stuff I picked up at Radio Shack, usually on sale. Two have RS-232 computer ports. That feature has been obsolete for a decade now, and I never used it. One has a capacitance range which I frequently use.
I also got by with a 300-watt solder gun for years - inherited from my Dad's workshop long ago. Clumsy but worked. Finally my wife bought be a good solder station... :^)
I'm just sayin' you don't need the fancy stuff - it's nice but you don't NEED it.
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Thanks Paul, that was the answer I was hoping to hear. I, too, am not fond of buying things until I know I need them. I doubt I will be building anymore kits after the Crack, but if I do then it doesn't hurt to wait to buy a proper one until then.
So what do you suggest doing when I need to measure those low AC volts? Just hope that I've done everything right and move on?
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I had thought that was the advice that I had given in the first response. Buy a cheap one now and if you continue with this hobby you will want a better meter. The example of a $55 Fluke is for the future. As I said of the HF meter, "For $5 you can't go wrong."
P.S. See my modification of reply #1 above for a great HF charcoal starter, a must for all BBQ fans.
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So what do you suggest doing when I need to measure those low AC volts? Just hope that I've done everything right and move on?
The meter will measure lower AC voltages, it just might not give a result out to as many decimal places as a lower range setting might on a meter that has those lower ranges. Might not work for measuring millivolts, but it will be fine for your purpose as all you might want to measure is the 6.3VAC heater supply.
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Thanks, Doc.
And since I already have a thread up, I thought I'd ask the question here:
I might be missing the 270ohm 5W resistors, unless they're green now?
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Thanks, Doc.
And since I already have a thread up, I thought I'd ask the question here:
I might be missing the 270ohm 5W resistors, unless they're green now?
They are green now.
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I think the ones in my Eros were green. I did scratch my head then measure with my meter.
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Green, round and long wirewounds? Or metal oxides? Just curious.
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They are not metal oxide. They are Vishay Draloric 5 Watt wirewound resistors with ceramic centers and a cement coating.
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Parts Express is having a sale, there's a multimeter for $2, #399-002.
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I've used flukes since 1984. I have replaced the batteries twice, blew a fuse once. I have never even questioned the reading I have gotten. Poster Paully has this one (I think):
http://www.ebay.com/itm/Fluke-15B-Auto-range-Digital-Capacitance-Inductance-multimeter-meter-Test-17B-/220868418663?pt=LH_DefaultDomain_0&hash=item336cc89c67
$55 +shipping is a good price.
Why are all the 15B flukes on ebay from China? Any idea if they are real flukes or copies. Just seems strange that they are only offered from chinese sellers.
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Parts Express is having a sale, there's a multimeter for $2, #399-002.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=399-002
Is it any better than the one I have now?
Also, how essential is it to bend the leads of the resistors at the specified length? After 6 hours of working on this, I got tired and skimmed the instructions when I got to the resistors - what a mistake! My resistors are curved into the terminals they need to be in rather than right-angled, and not necessarily at the right length either. Will this affect anything?
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For $2, I would think of getting one for a back-up, if I didn't already have enough back-ups.
If I understand your question about the resistors, you should be fine. Just make sure you understand the instructions and follow them. If you run across one you don't understand, just post a question here.
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Got through the resistance readings just fine with the $5 HF multimeter, except some readings in the 2.4K and 2.9K came out 100ohms higher. I also couldn't figure out where I would measure for the 90K-100K range on the RCA plugs, so I skipped that. After I hooked everything up to power, the fuse blew :|
It's gonna be a long night!
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Got through the resistance readings just fine with the $5 HF multimeter, except some readings in the 2.4K and 2.9K came out 100ohms higher. I also couldn't figure out where I would measure for the 90K-100K range on the RCA plugs, so I skipped that. After I hooked everything up to power, the fuse blew :|
It's gonna be a long night!
Your 100 ohm higher readings on the two resistors are fine, well within the 10-15% variation. I dont have the manual handy but I believe it states to turn the volume all the way down. Doing that and with meters ground/black probe connected to a ground, touch the red probe to the center pin of each of the RCA jacks, first one then the other. Assuming you used the kits included wire, the center pin would be the solder cup of the RCA jack where you soldered the red wire (for the right/red jack) and white wire (for the left/black) rca jack. First check one, then the other. This basically checks the wiring from the jacks to the volume control pot as well as indirectly checking the pot. With the "volume" turned all the way down, the pot measures about in the 90-100K range and this should be what you measure at the jacks give or take a little either way. There will probably be some variation between the measurements of the left and right jacks. That's ok, the pot isnt perfectly matched between sections.
Do you have any spare tubes of both types used in Crack? It's probably not a bad tube causing your blown fuse but it isnt uncommon. If you got through the resistance checks ok and you do have spare tubes, try those first and see if the fuse holds up. Radio Shack probably has spare fuses if you dont have any. I believe it's a .5 amp fuse, take it with you and you can match it up.
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Blown fuses are most often caused by diodes being reversed or the power supply caps being reversed.
Look in your manual at page 27. Observe the band on the diodes. Check the two from T18 to T20 and T18 to T21. Check the two from T19 to T20 and T19 to T22.
For the capacitors look at T20, it should be the white stripe of the cap, look at T14 that should be the white stripe and finally look at T13 that should be the white stripe.
These are the most often causes of blown fuses. If you got a capacitor reversed it is probably blown now.
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Grainger is the man as usual, so heed his words of wisdom fellow grasshopper :-)
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Blown fuses are most often caused by diodes being reversed or the power supply caps being reversed.
Look in your manual at page 27. Observe the band on the diodes. Check the two from T18 to T20 and T18 to T21. Check the two from T19 to T20 and T19 to T22.
For the capacitors look at T20, it should be the white stripe of the cap, look at T14 that should be the white stripe and finally look at T13 that should be the white stripe.
These are the most often causes of blown fuses. If you got a capacitor reversed it is probably blown now.
Problem found! I seemed to have shifted a capacitor, the striped side that should be in T20 is in T19 instead...does that mean I've fried it? I will try resoldering it and report back. Thanks!
EDIT: It works! :D Thanks so much!
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If the leads were swapped it is weakened and will fail. If it was just on a wrong terminal, not swapped, you should be ok.
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Everything is sounding great, I just hooked everything up and no problems at all! It's amazing how bad I am at DIY projects and how easy this was to put together!
Should I be feeding it through the headphone jack of my sound card or the line out? I have an Auzentech Forte card, so the headphone out is amplified. I'm assuming the line out would be the better choice?
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Yep, line out is the better choice.