DIY Alignment and Calibration

[QuadMusic]

Can't find Winscope anymore.

It's available at http://madan.wordpress.com/2006/06/2...-winscope-251/

PC

[lo.fi.love]

OK, I asked a question about voltmeters, I got this response:

A good AC voltmeter that can read down to 20 mv and has a bandwidth of 150Khz.

Please pardon me for being confused, but I don't know how to look for such a thing. "How do I search for a voltmeter with these specifications?" is a question that I can't answer.

Can someone point me in the right direction by posting a product link? I'll really appreciate it.

[ofajen]

OK, I asked a question about voltmeters, I got this response:



Please pardon me for being confused, but I don't know how to look for such a thing. "How do I search for a voltmeter with these specifications?" is a question that I can't answer.

Can someone point me in the right direction by posting a product link? I'll really appreciate it.

I have an HP 403B. It gets the job done.

Otto

[sweetbeats]

IMHO 150kHz bandwidth is overkill for doing an alignment. Jeff, what I think you want to look for is a voltmeter that is rated from 20Hz to 20kHz with limited error within that range. Any of the Fluke 83/85/87 meters will do nicely for that and are pretty plentiful on the used market. Any of the analog meters mentioned above will do too, but if you get a meter that has a rating in the "audio" band range it'll work for you too. You can download manuals for the Fluke meters on their website to confirm bandwidth.

If you are having bias issues then having higher bandwidth is important because bias tone is typically 100kHz, 150kHz or even 250kHz. But if you are having trouble there then its time to have a scope and such. That's my limited personal experience.

BTW everybody evm1024 turned me on to TrueRTA, a freeware analyzer/scope/meter for PC...the coolest freeware program like this I have ever seen. It'll help folks that are on a budget pinch for sure or don't need such utilities frequently and can't justify springing for hardware counterparts.

One thing to add about using sync or repro heads. It depends on the design of the machine. As a rule the repro head is better, but Tascam broke that rule with a few of their decks. Machines like the 38 and 48, use the same part number for both sync and playback heads. So, you don’t get the same advantage by using the repro for playback as you would with a machine that has a specially designed Repro head.

Yep...and others followed suit. 58 is the same way. Only need met and advantage gained on such sytems is having the repro head there for on-the-fly bias adjustment and other diagnostics. It becomes little more than a convenience feature...nice one though.

[evm1024]

Jameco sells a number of meters. This link is to the spec sheet of one of the meters that they resell (they have a nice selector as well)

You can see the spec under the "AC volts accuracy" heading 5% for the 10 to 20 KHz range....

http://www.jameco.com/Jameco/Product...DS/1581214.pdf

I'm not recommending this meter (it does look nice) it was just the first one that I get the specs from.

Regards, Ethan

Here is the interactive selector:
http://www.jameco.com/webapp/wcs/sto...%20Multimeters

[Victory Pete]

OK, I asked a question about voltmeters, I got this response:



Please pardon me for being confused, but I don't know how to look for such a thing. "How do I search for a voltmeter with these specifications?" is a question that I can't answer.

Can someone point me in the right direction by posting a product link? I'll really appreciate it.

If you have a 2 head deck like TSR-8, MSR16, or MSR24 the easiest way to set the bias is by adjusting the trim pot for the bias circuit voltage, In the case of the TSR-8 it is 35 mv at 150Khz. A 3 head deck is easier to adjust because you monitor the rise and fall of a 10Khz tone on the decks meters. I have a Fluke 8060A, an HP 3400A, HP 400D tube job, HP400E, and HP400EL. I bought them all on an e-bay binge one weekend. The best one is the Fluke 8060A it was one of Flukes first digital meters. I actually have 2 and they both read the same voltage together within .0001v. The Fluke 8060A can do it all. The other HP's are all analog ac powered. Sometimes it is better to watch a needle instead of digits. Check e-bay and goodluck!
VP

[miroslav]

BTW everybody evm1024 turned me on to TrueRTA, a freeware analyzer/scope/meter for PC...the coolest freeware program like this I have ever seen.

What's the difference between their "levels"?
I see that only the TrueRTA level 1 is freeware...the other levels are not...but they are not too expensive.
I'm just wondering if Level 1 gives you all that you need for alignments and basic analysis.

This one that I posted earlier is total freeware, and I liked how it worked overall.

Visual Analyzer

http://www.sillanumsoft.org/

[lo.fi.love]

OK, it's one of those rare nights where I have access to a computer for the entire evening. My computer broke down almost three months ago and I just really haven't had any desire to replace it... ironic, considering that I'm a web programmer...

Anyway, I'm moving along in a number of projects. I'm about ready to start ordering some things off the Web. I wanted to run this by everyone here before I make the purchase:

250 nWb/m MRL tape for a TASCAM 34b. Is this right??

I think this is what the manual says but I want to be 100% sure.

[evm1024]

OK, it's one of those rare nights where I have access to a computer for the entire evening. My computer broke down almost three months ago and I just really haven't had any desire to replace it... ironic, considering that I'm a web programmer...

Anyway, I'm moving along in a number of projects. I'm about ready to start ordering some things off the Web. I wanted to run this by everyone here before I make the purchase:

250 nWb/m MRL tape for a TASCAM 34b. Is this right??

I think this is what the manual says but I want to be 100% sure.

That is the standard in the US more or less. If I were buying a new MRL I would get a 250 nWb/m .

Plus you can "adjust" the readings that you get to calibrate at pretty much any flux level. I'm answering in your other post too.

--Ethan

[cjacek]

.....great work guys!