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Pioneer RT-707 Recap + Head Relap

It took me a few reads to understand 11.2 but I figured it out so let me know if you get stuck.
 
My frequency response measurements are good .Its my play back level . My cal tape is 250nWb/m so I can't set the deck to 0db with it .Do you how much above 0db I should set it when using the 250nWb/m ? Pioneer decks use 160nWb/m right?
 
Calman,

Let's take this step by step and see if we can figure it out. It may be a bit tedious but bear with me.

I believe my calibration tape is the same as yours. Is your tape 1/4" 7.5 IPS NAB 6 Minute 250 nWb/m MRL21T204?

Let's start with step 11.1

I'm not sure it says this anywhere but before you start, set the line level output controls on the back of the unit to the center position.

Assuming your tape is the same as mine, play back the first test frequency of 1000 Hz at 0dB. Ignore what is on the RT-707's VU meters. Can you set VR 105, 106, 107 and 108 to get 450mV at the output terminals for L & R forward and reverse playback?
 
yes I have the MRL 21T204. I have 450mV for L&R Forward and reverse playback. I got mixed up with setting the meters with the tape ,you don't .
 
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Step 11.2

Ok, now I believe the next 2 frequencies on the tape are 500 Hz and 8000 Hz at -10 dB. (I know the test calls for 700Hz and 10000Hz but I think it's fine.)

When you play back 500 Hz, you will probably get somewhere close to 150 mV at the output. Then when you play the 8000 Hz tone, you need to adjust VR 101, 102, 103, 104 to ensure you get the same value that you got at 500Hz (again, probably close to 150 mV).
 
calman46 said:
There is a 10k tone . Is better to use the 8kHz with the 500Hz? Will do
Click to expand...

I used the 500 Hz and 8000 Hz simply because they are recorded one after the other and that made it easier to do the settings 4 times (L, R, Fwd, Rev). Plus I'm happy with the results.
 
calman46 said:
I got mixed up with setting the meters with the tape ,you don't .
Click to expand...

Calman, I just reread this and think I understand where you went wrong. Were you using the signal on the tape to do step 11.3? If so, I understand what happened. I believe you figured out that you need to use a signal generator for this step as opposed to the tape. What are you using for a signal generator? I used the one built into my Pioneer SD-1100.
 
Step 11.3

Great. Now take your calibration tape off.

Feed 1000 Hz into the inputs (I used a mono to stereo splitter to do this so that I knew exactly the same signal was being fed into Left and Right)(the amplitude doesn't really matter but I used 450 mV). Hook your meter up to one of the outputs. Set the monitor switch to source. Make sure the left and right portions of the input control on the front are lined up. Adjust the line input control on the front until you get 450 mV at the output. Then adjust VR109 (L) or VR110 (R) until the coresponding front panel meter reads 0dB. Then you'll need to do it again for the second output.

Now your playback level, EQ and VU meters should be set correctly.

Try some music to see how it sounds to decide if you want to do any of the other adjustments.
 
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Yes I have splitter also . I have to turn the amplitude full on or output of the deck is not even ,it was driving me nuts. I'll run cal tape a few more times and then play music . Thank you for your help ,maybe I will do the recording part.
 
Well it sounds great . I'm using an upgrades Moscode 600 /Minuet in A preamp with Von Schweikert VR4 speakers .I haven't recorded yet maybe this weekend.
I have this issue with my RT 909 also. When I play prerecorded tapes one side shows weaker on the VU meters, when in reverse play its the opposite channel that is weaker. I don't think I would notice if I didn't look at the meters they sound fine. Is there any relay when switching the play directions the would effect the audio output, I looked but didn't see one. Or this could just be 70's tech and that is the way the tapes were recorded.
 
Thats what I thought. But the azimuth and tilt etc..look good . This is only my second time at calibration . I'll look at them again.
If I record with the deck(s) and playback levels are even ,what does that means?
 
I believe, and someone smarter than me can weigh in, that the tapes you are recording on the deck, when you play back on the same deck are OK because they are "equally misaligned", if you will.
 
Assuming the record head is misaligned. Anyway its real close but something is happening in the left, I get meter needle fluctuations and when setting the VU level with the 1Khz on the input,the output of the deck is not even. All the steps before this are good.
 
Are these pre-recorded tapes ones made by you on another deck, or factory produced? If factory, i'd say yes, there is a problem. If homemade, then it's most likely they were made out of balance. If you have followed the calibration procedures discussed above and everything comes out where it's supposed to with the MRL tape, then your machine is just fine. Its the tapes that are off, and you can't do anything about that.
 
The tapes are factory ,the calibration is good up to setting the VU meters. When I feed in the signal and turn the line in pot for 450mV the L&R are different ,if the right is a 450mV the left is at 380mV on the volt meters connected to the outputs. The deck does record but the channels are uneven because of this imbalance. So I'm looking at the record level maybe off.
 
Just to be clear, you are talking about issues with your RT-909 correct? I just want to be sure that people don't think you recapped your RT-707 and that there is now something wrong with it and by extension, the recap list in this thread.
 
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