jpmorris
Tape Wolf
What you might want to do is generate a stereo sinewave on a PC, using audacity or something. If you feed in the left and right channels you should get the perfect diagonal line so you can check the scope is behaving correctly.
ron-e-g
Member
Jp,
Wouldn't this do the same thing?
Ron
Wouldn't this do the same thing?
Ron
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fgonza2
New member
fgonza2,
Just to eliminate any confusion. You mention to disconnect the probe. By this do you mean the RCA cable's connecting the recorder to the scope CH 1&2? Put in in Channel 1 only mode in the Vertical section, or the trigger section? By "pos" knob do you mean position? And position 1 first then switch to Channel 2 and do the same?
b= set the volts/div knob to;100mV. Would that be .1 on the dial(s)?
By "now after that" do you mean set the sec/div knob to y/x?
What change are you referring to? the change as the test tape goes from the 1khz to the 10khz?
Lastly..what pictures don't load? Sorry to be so confused. I'm easily confused!
0. Make sure to calibrate playback levels first with the calibration tape (both repro and sync head)
1. Put them in GND mode
2. Use the position knob (vertical) to make sure the ground is at zero. Not trigger, dont change anything in there.
3. Ok to not disconnect if you use the GND mode.
4. Do this for both channels
5. Yes .1 on the dial
6. After this go to XY mode
7. Yes, change in the test tape from 1khz to 10khz
8. As suggested by jpmorris, you can use the generator first and connect it to inputs 2 and 15, then put it in input monitor mode, and you should see a perfect 45 degree line (make sure the generator output is at 0.3V rms), so you can make sure the setup is correct. If it is not 45 then your levels are off somewhere either on the generator or in the input circuitry calibration. (post picture)
9. After that switch to repro mode and you will see the ellipse (with the 1khz tone it will be nicer) look at it with 10Khz and 16khz tones on the tape, post pictures.
10. Repeat with sync head
I can see the pictures now
let us know how it goes. Did you setup levels already ? how did you measured it ?
jpmorris
Tape Wolf
If it can generate two identical outputs for the left and right channels, yes.
ron-e-g
Member
These are the settings/connections, and image on the scope.
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fgonza2
New member
what is the RMS value at the output of the generator ? looks like it is too high and you are getting off range in the scope
ron-e-g
Member
I've adj. the generator output as seen.
in input mode
in sync mode
in repro mode
Connections
in input mode
in sync mode
in repro mode
Connections
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fgonza2
New member
the RMS meter needs to show -10 on the green scale. which is the -10dbV or 0.316 RMS. That will be the same level that you need to adjust the playback cards when running the calibration tape on both repro and sync mode.
How do you find the AQ-65 ? i am missing one for my MS16. Currently in the process of building an iPad remote control for these machines.
How do you find the AQ-65 ? i am missing one for my MS16. Currently in the process of building an iPad remote control for these machines.
ron-e-g
Member
Thanks for that fgonza2,
What bothers me, is when I switch from input to sync to repro I see no Oval or..ellipse. I must be overlooking something.
The AQ-65 is a great option to have. Allows the user to have better access to the recorder. And adds a few more options. What I can't figure out, is if there is a user manual for the AQ-65, or just the minimal information in the MS-16 manual.
How is the iPad project going?
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fgonza2
New member
on repro and sync:
1. You need to connect the channel outputs to the scope (2 & 15)
2. You'll only see something when the tape is being played - no generator here, as you are looking at the tone in the tape. The generator setup is useful for the input level alignment and later for record adjustments, bit not for playback.
3. I dont have an AQ-65, but i looked for one for a long time and for the manual as well with no luck. It should be not too hard to figure out the functions. But i haven't seen a manual ever.
About the iPad project is going well. It just ended up being a big software project, so it is taking a while as i can only work on it during my free time. But i can now also control the speed. So we i'll be able to run the MS16 at 30ips with it as well or even 7.5ips with no mods. I will post a video update soon, i am currently working on the wifi part.
1. You need to connect the channel outputs to the scope (2 & 15)
2. You'll only see something when the tape is being played - no generator here, as you are looking at the tone in the tape. The generator setup is useful for the input level alignment and later for record adjustments, bit not for playback.
3. I dont have an AQ-65, but i looked for one for a long time and for the manual as well with no luck. It should be not too hard to figure out the functions. But i haven't seen a manual ever.
About the iPad project is going well. It just ended up being a big software project, so it is taking a while as i can only work on it during my free time. But i can now also control the speed. So we i'll be able to run the MS16 at 30ips with it as well or even 7.5ips with no mods. I will post a video update soon, i am currently working on the wifi part.
ron-e-g
Member
Yea, I have both connections at the same time. I have the generator, and meter connected to the inputs and the scope to the outs. But as you see... not viewing the ellipse. Must be a setting to change on the scope. ?
Wow..running the MS-16 @ 30 ips with no electrical changes required! That should be worth it's weight in Gold! Mine was factory set to 30. I inquired about setting it back to 15 and was told "it would be a lot to change".
Wow..running the MS-16 @ 30 ips with no electrical changes required! That should be worth it's weight in Gold! Mine was factory set to 30. I inquired about setting it back to 15 and was told "it would be a lot to change".
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fgonza2
New member
So, for repro and play. disconnect the generator and connect the audio outputs of the recorder in its place, channel 2 of the recorder to channel 1 of the scope and channel 2 of the recorder to channel 15 output in the recorder. In repro mode if you press play you should be able to see something. Just connect the recorder outputs directly to the scope, and that's it.
About the speed, there is an external way of controlling the capstan speed, which is what synchronizers used, i am using that input to do so. So in theory yours should be able to run in 15 ips by using this as well. 30 ips eats a lot of tape fast.
ron-e-g
Member
First..30 ips does cause the disappearing supply tape syndrome! 
OK, so to be sure before I start monkeying around with the azimuth on my machine.. BTW I don't disconnect the test equipment from the input I only leave it turned off. Is that a problem?
This is how the scope is set-up;
This is 1 kHz;
This is 10 kHz;
This is 100 Hz;
This is 100 Hz With the "beam finder" engaged on the scope;
OK, so to be sure before I start monkeying around with the azimuth on my machine.. BTW I don't disconnect the test equipment from the input I only leave it turned off. Is that a problem?
This is how the scope is set-up;
This is 1 kHz;
This is 10 kHz;
This is 100 Hz;
This is 100 Hz With the "beam finder" engaged on the scope;
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fgonza2
New member
ok, so is this in repro or sync mode ? is the scope in the same voltage scale for the three pictures?
What i can see, assuming you have the right connections and the same scope scale on all pictures
1khz - not too bad - but it doesnt show the real situation
10khz - Significant phase difference - azimuth is bad
100hz - looks ok, again not a reference for azimuth
So in the end you do have an azimuth problem, does your MRL has a 16Khz tone ? if so, it will get worse, Sometimes you will see a good 10khz setting but not a 16khz. The azimuth should be adjusted with the highest frequency tone possible available on the calibration tape, when you do that, you will see that the lower frequencies will look very good. So concentrate in the 10khz or 16khz tone if you have it. What calibration tape you have ?
Now, i can also see that you have a frequency response issue in your recorder. This is evident by looking at the "radius" of the ellipse which is basically the signal level. If you look at the RMS meter you will see how the level drops as you go up in frequency. 100 hz is the highest due to head bump, 1khz is ok, then 10khz goes down significantly. Take the measurements of the levels in repro mode with the RMS meter. Look at the green scale and report back for each tone. They should be within +/- 2db. You can try doing some adjustment on the playback levels, as that will give you a better baseline for the azimuth adjustment.
So be patient with the azimuth adjustment and make sure you have the proper metric allen wrenches for adjusting them, those screws are small, and easy to break. Go slowly and adjust both to get a stable state.
About your other question:
There should be no path between the outputs of the recorder and the generator. Meaning no Y-cables between scope inputs and generator output at all. If you are doing that you may blow your recorder output. So disconnect the generator. There should be cables only from the output of the recorder to the scope input channels and the Y-cable to the RMS meter, to monitor levels, nothing else. The Y-cable if connected to the generator output and the recorder output will load the outputs with a very low impedance that can damage your recorder.
What i can see, assuming you have the right connections and the same scope scale on all pictures
1khz - not too bad - but it doesnt show the real situation
10khz - Significant phase difference - azimuth is bad
100hz - looks ok, again not a reference for azimuth
So in the end you do have an azimuth problem, does your MRL has a 16Khz tone ? if so, it will get worse, Sometimes you will see a good 10khz setting but not a 16khz. The azimuth should be adjusted with the highest frequency tone possible available on the calibration tape, when you do that, you will see that the lower frequencies will look very good. So concentrate in the 10khz or 16khz tone if you have it. What calibration tape you have ?
Now, i can also see that you have a frequency response issue in your recorder. This is evident by looking at the "radius" of the ellipse which is basically the signal level. If you look at the RMS meter you will see how the level drops as you go up in frequency. 100 hz is the highest due to head bump, 1khz is ok, then 10khz goes down significantly. Take the measurements of the levels in repro mode with the RMS meter. Look at the green scale and report back for each tone. They should be within +/- 2db. You can try doing some adjustment on the playback levels, as that will give you a better baseline for the azimuth adjustment.
So be patient with the azimuth adjustment and make sure you have the proper metric allen wrenches for adjusting them, those screws are small, and easy to break. Go slowly and adjust both to get a stable state.
About your other question:
There should be no path between the outputs of the recorder and the generator. Meaning no Y-cables between scope inputs and generator output at all. If you are doing that you may blow your recorder output. So disconnect the generator. There should be cables only from the output of the recorder to the scope input channels and the Y-cable to the RMS meter, to monitor levels, nothing else. The Y-cable if connected to the generator output and the recorder output will load the outputs with a very low impedance that can damage your recorder.
ron-e-g
Member
A. The mode is set to repro.
B. Yes, no change of scope settings
C. My MRL does not have the 16kHz tone
D. Test tape is 30 ips. AES (IEC2) Eq. 355 nWb Ref. Fluxivity Three frequency all @0 db.
I have observed a big drop in the recorders VU's when it changed from 1kHz to 10kHz.
As for the connections.. the only thing I have ever connected to the outputs of the recorder have been the inputs of the scope. The only thing ever connected to the recorder inputs have been the generator and meter.
I will connect the meter to the outputs and report back.
B. Yes, no change of scope settings
C. My MRL does not have the 16kHz tone
D. Test tape is 30 ips. AES (IEC2) Eq. 355 nWb Ref. Fluxivity Three frequency all @0 db.
I have observed a big drop in the recorders VU's when it changed from 1kHz to 10kHz.
As for the connections.. the only thing I have ever connected to the outputs of the recorder have been the inputs of the scope. The only thing ever connected to the recorder inputs have been the generator and meter.
I will connect the meter to the outputs and report back.
ron-e-g
Member
Hum..when I check the meter range set to position 1 (right). I get a reading of -12 @1kHz then not even registering @ 10kHz!
When I set to MV 300 (left) I get a reading between 0 and -5 dBV @ 1kHz and -17 @ 10kHz!
When I set to MV 300 (left) I get a reading between 0 and -5 dBV @ 1kHz and -17 @ 10kHz!
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fgonza2
New member
so you have bigger problems than azimuth at this point. So, let me suggest the following:
1. You have a 355 nwb/m that is a +3db cal tape. What tape are you using ? ATS, RMGI SM911? you want to bias your machine for the right tape.
2. So first try to calibrate your machine on play mode. Only connect the RMS meter to the output and when in play @ 1khz tone. Adjust the playback levels as per the manual, using only the RMS meter
3. As you are using RCA and not XLR. Your levels are not 1.23V for 0db, as the manual says in 7-6-2 or 7-6-5 (reproduce level calibration). It will be -10db for 0dB which is the -10 on the green scale or 0.316v RMS. This is not stated in the manual as they assume that you are using XLR.
3. When on the 10khz tone, adjust the playback eq to get it close to the same 0db level (0.316v) this is all in the "1" scale in your leader RMS meter.
See how flat can you get the freq response on repro and sync mode. You have to do this for the 16 channels for both sync and repro mode. So this will take some time.
After that we'll go back to azimuth. By the way, how are your heads? can you post a close picture ? use a blank sheet of paper to control reflection.
By the way, check out the pictures of my MS-16 restoration. almost done.
https://plus.google.com/photos/104155858161686012634/albums/5776284243478106625?authkey=CL7j1vW7mJ-ZvwE
1. You have a 355 nwb/m that is a +3db cal tape. What tape are you using ? ATS, RMGI SM911? you want to bias your machine for the right tape.
2. So first try to calibrate your machine on play mode. Only connect the RMS meter to the output and when in play @ 1khz tone. Adjust the playback levels as per the manual, using only the RMS meter
3. As you are using RCA and not XLR. Your levels are not 1.23V for 0db, as the manual says in 7-6-2 or 7-6-5 (reproduce level calibration). It will be -10db for 0dB which is the -10 on the green scale or 0.316v RMS. This is not stated in the manual as they assume that you are using XLR.
3. When on the 10khz tone, adjust the playback eq to get it close to the same 0db level (0.316v) this is all in the "1" scale in your leader RMS meter.
See how flat can you get the freq response on repro and sync mode. You have to do this for the 16 channels for both sync and repro mode. So this will take some time.
After that we'll go back to azimuth. By the way, how are your heads? can you post a close picture ? use a blank sheet of paper to control reflection.
By the way, check out the pictures of my MS-16 restoration. almost done.
https://plus.google.com/photos/104155858161686012634/albums/5776284243478106625?authkey=CL7j1vW7mJ-ZvwE
ron-e-g
Member
I use GP9 tape.
As for the heads; https://homerecording.com/bbs/general-discussions/analog-only/last-2-head-shots-paper-trick-352233/ Post #4 ( they actually look better now with a better cleaning!
What range should I set the Leader Meter to when I make these adj.?
I have viewed your progress on that project. It's great! Wanted to ask. What paint did you find to be the best match?
Ron
As for the heads; https://homerecording.com/bbs/general-discussions/analog-only/last-2-head-shots-paper-trick-352233/ Post #4 ( they actually look better now with a better cleaning!
What range should I set the Leader Meter to when I make these adj.?
I have viewed your progress on that project. It's great! Wanted to ask. What paint did you find to be the best match?
Ron
Last edited:
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fgonza2
New member
i remember now. yes those heads look nice. you shouldn't have any issues adjusting the playback levels. Put the meter in the "1" scale. I have the paint code from home depot. i am at work, when i get home tonight i'll send you the code, so you can go to your home depot and get that, it matches perfectly.
ron-e-g
Member
Ok, Thanks. BTW I assume you mean this "1"?
