*NOTE ON REPRO ALIGNMENT TONES: A typical MRL alignment tape may be recorded @ 250 nwb/meter or "+3" level. So, if an operating level of +3 is requested, the repro level would be set to 0 VU with this tape. If an operating level of +6 is requested, the Repro level is set to -3 VU (all record levels are set to 0 VU). This procedure applies only to MRL tapes. Client's printed tones are always set to 0 VU.
IMPORTANT! - There are two sets of calibration controls for each channel on this machine. The pots with the large screwdriver slots (originally these were covered with plastic caps) are strictly for calibrating internal electronic levels. These should not be changed! Only the smaller pots (on the removable channel modules) are to be used in the following alignment procedures.
1. If needed, demagnetize heads (machine off). Clean with isopropyl alcohol (at least 91% pure is preferable). Make sure all the roller guides on both take up & supply sides are clean.
2.On remote unit, select the master Repro switch. Check that all gray channel switch levers on the machine are set to "Repro". These levers should remain in this position during & after the alignment. The control knob on the far right on each channel on the machine should be set to "Rem".
3. Select desired tape speed (on machine). If your remote has one, press the Master Safe (Rem C) switch. If not, make sure each individual safe switch is up so all channels are in safe mode.
4. Thread up an MRL test tape or client's printed tones.
5. Using the 1 KHZ tape tone, adjust the small Level pots (on Reproduce Adjustment channel modules) for the appropriate speed; Fast = 30 ips or Slow = 15 ips, for -3 VU (with MRL tones), or 0 VU (client's tones)*.
6. Press master Sync switch on the remote. Using 1 KHZ again, adjust Sync Level pots in the same manner as step 5.
7. Press master Repro switch. Play the 10 KHZ tone and adjust the Repro High Frequency Equalization pots for the appropriate speed using the same level as in steps #5 & #6. Now, repeat step 6, using 10 KHZ to adjust Sync High Frequency Level.
8. Route an oscillator tone @ 10 KHZ to all inputs. If you are using a mixer's busses (group outputs), make sure the console is in buss or "group out" mode and not in tape return mode.
9. Set all channels to record ready (depress the Master Safe switch if present) and thread up a blank reel of the tape type you will be using. Place machine in record.
10. Set oscillator level for an indication of about mid-scale on the A80's meters.
11. Set each track as follows: Turn Bias Level pot (for the appropriate speed) back & forth until a peak is found. Now, turn pot clockwise until meter drops by 1.5 dB (VU) @ 30ips, or 3 dB @ 15 ips. These settings are for Quantegy/Ampex 456, Agfa 468, RMG/Emtec 911, ATR Services tape, and the old 3M 250/226 tapes. For Quantegy/Ampex 499, use 1.75 dB @ 30 ips, or 4 dB @ 15 ips. For RMG/Emtec 468 & 900 tapes, use 1.5 @ 30 ips, or 4 dB @ 15 ips. For RMG/Emtec 911 tapes, use 1.5 @ 30 ips, or 3 dB @ 15 ips. For 3M 996 tape, use 2 dB @ 30 ips, or 4 dB @ 15 ips.
12. Change oscillator frequency to 1 KHZ. Verify that your source is feeding a zero level (+4) to each channel on the A80 (if you are using a board as the source, carefully set each of the board's buss outputs to exactly 0 VU on the console buss meters).
13. Press master Input switch on remote. All channels on machine should indicate 0 VU. If any are not set to zero, the small "Record" pot next to the gray switch lever on each channel can be adjusted (these pots are usually pre-set to the correct level & should not ordinarily require re-adjustment).
14. Press master Repro switch. Place machine in record and adjust each Level pot (on plug-in record adjustment modules) for 0 VU on the machine's meters. Do not adjust the Erase Amp pots! Change osc. frequency to 10 KHZ. On record modules, adjust High Frequency Equalization (for the appropriate operating speed) to 0 VU.
15. Change oscillator to 100 HZ. With deck in record and master Repro switch on, set Low Frequency Equalization reproduce pots (for the appropriate speed) to 0 VU.
16. Print at least 30 seconds of 100 hz tone on all channels.
Press master Sync switch. Rewind tape and playback tones. Set all Low Frequency Equalization Sync pots (for the appropriate speed) to 0 VU.