MS16 Calabration

  • Thread starter Thread starter ron-e-g
  • Start date Start date
if that is 10Khz, the first picture is pretty good. the second one is bad, significant phase difference.
 
Are the Repro and Sync heads supposed to be at different angles? I've noticed at a certain point in adjusting the ellipse will change it's angle of orientation.

My Daughter just moved from Sac. I have a Brother in Lodi, and a Son in Stockton. I lived in Stockton for 23 years!
 
No, the angle should be the same, from lower left to upper right.

Use the 1Khz tone for the initial azimuth adjustments (course). Get the display (sync and repro heads) as close to the straight angled line as you can by adjusting the azimuth adjustment screws on the head block..

Then use the 10Khz tone for final fine tuning of azimuth. It is really touchy, you will see......

Does your reference tape have a 16Khz tone? If so you can check your work with that tone after completing the above two alignments.
 
OK, good to know. My cal. tape is 1k ,10k, and 1Hz. I have already experienced that touchy thing!:thumbs up:

Thanks mdainsd.
 
if that is 10Khz, that is pretty good, and it doesnt get much better than that. You ar good to go. I am guessing the second video (the one with no opening) is the 1khz. If it is 10Khz, your recorder has a extremely well working transport. Anyway i think you are already there if that is 10Khz. You can reduce the intensity of the scope to get a little more clarity. But as i said before. Mission accomplished. :thumbs up:
 
Thanks fgonza2 And mdainsd for ALL You guy's help. Hopefully this thread will also help someone in the future (everyone else probably already knows) who may find themselves in a similar situation. I know I've learned a lot. And, only scratched the surface. But, there is a lot of good stuff (some not so good) on my part, in the previous post. I list this under "all you wanted to know about calibration but, were afraid to ask!" category.;)

So it's off to Bias adjustments and, Record input. Should be cake!
 
Well I didn't get off vary far! I went out to set-up the scope for a 10k signal to adj. the bias. No trace... only a chirping sound...and dull flash from the trigger light!

So I need a 10 kHz,-1db (690 mV, -5 VU) signal. or whatever the conversion is for the RCA input. But I can't set it with the scope!

With what I have how would I do that. BTW I now have this View attachment 79159
 
ok, so what's next is BIAS and record levels. unload the calibration tape first and store it in a safe place. You will adjust now, the other stuff, like REC level, REC EQ and BIAS. What you have in the picture is a frequency counter, you can use it to adjust the output frequency of the generator. Follow the manual to adjust BIAS and post any questions.
 
So I need a 10 kHz,-1db (690 mV, -5 VU) signal. or whatever the conversion is for the RCA input. But I can't set it with the scope!
Click to expand...

How can I achieve that?
 
Would I input the generator to recorder input, than output from recorder to RMS meter, switch to input mode and adj. the shine knob on the generator to read -5 db on the recorders VU?

And record that signal to set BIAS, REC INPUT, and REC EQ.?
 
yes, that is one way. I don't remember the -5db being mentioned in the manual like that, are you sure on that one ?
 
Yea, I wrote it exactly how the manual did. You think it matters how hot the signal is. I mean weather it's -5 or 0db on the Recorders VU?
 
I tried a simple record test today. Same as I did prior to my calibrations.
Recording is terrible! And to top it off... now track 2 wont erase! Maybe more, I only recorded to track 1&2. I can still hear the recorded music, and even the tone I used to set the bias.
I only had the first two tracks armed for recording but there seem to have been leakage to track 3 also.

Any Ideas at this point? Man, I need some help! Please...
 
ok, lets recap. questions:

1. Did you finished the BIAS adjustments as per the manual ? did you do the 0dB on the VU meter, etc ?

2. Did you touch the BIAS trap adjustments ?

3. Make sure the erase head is well connected - it has a blue connector

4. When you record nothing (no input signal) can you hear all of the previous signal ? or a lower level version ?
 
I did some more investigations last night. It seems track 2 is the main problem. I tried recording track 1&3. I got the same disjointed sound. then I eliminated track 2 and the sound is real good on 1&3! I have another problem (I'll deal with later) the console only receives sound from the Tape Returns on the left Master Channel.

I will admit something now. That probably will have importance at this point. When using the Card Extender at some point in the cal. process I installed it one time with the pins off by one notch!
I didn't even know this was possible. But for others..BEWARE!

I caught it fairly soon after power back-on by noticing the recorders and RMS meters pegged. I shut off the recorder after no more than 7 seconds. I did smell what I can only describe as slight burning (maybe my imagination). After finding my mistake all seemed OK. I mean all calibrations went fine. At this point I felt I had dodged a bullet.

Trouble is..I can't remember what track that was. It could have been 2. I just didn't make a log of it.

To answer your questions: I did all the adjustments up to Record Level. Including Bias Level. (thats why track 2 still has the 10K tone slightly audible in my new record over Track 2)

I'm not sure what 0db you refer to.
I did not touch the Bias Trap as I felt it was not necessary. As I have not removed any heads ect.
I can record I do have input. track two has the lower signal along with a very distorted signal of the newly recorded signal.

I'm going to do a further test today. I will exchange card 2 for card 3 and see if the problem does indeed follow the card.

BTW I assumed the Bias level adj. are also done with the DBX off.

Ron
 
hi, yes DBX off always.

Swap cards and see if the behavior follows the cards. If there is distortion it may be BIAS related, we may need to revisit that procedure.

Try the following, record all tracks at the same time with a zero input signal (nothing connected) and see if erase works. If not there are two possible causes:

1. Sync/Repro head misalignment vs the erase head, so some track will erase and others won't or erase the adjacent track, you need to check head height alignment for this. Put the tape in and look closely in the head to make sure that is well aligned in the center. There is a possibility that this is a result of a not so optimal azimuth alignment. So take a look at that.

2. Erase not working fine in some channels due to electronics issue. This let me check the manual and look for some ideas. Try what i suggested above first.
 
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