hooking up otari mx5050 mkiii with tascam m520

[athuai]

Thanks for reply,
So the main question actually was/is:
Do you (or anyone here) have any idea how the ‘trimmers’ were physically set on these machines (this model) upon initially being made & leaving the Otari factory?
(machine would have been made new in 80s or early 90s)
& I’m definitely giving the 226 tape a shot…it’s totally new unsealed tape in great shape & there’s a bunch of people that have used same NOS type/batch to good effect recently.
Thanks!

 

[sweetbeats]

Please re-read my last post. The trimmers would not have been set according to some physical position standard. They would be set according to what is dictated by the procedures in the calibration section of the service manual using the required test equipment. This would vary from machine to machine when new. You can take any calibrated tape machine old or new and compare it to another of the same model a none of the trimmers will be the same. There might be similarities, but enough variation that it’s not wise to try and extrapolate “correct” trimmer settings based on somebody telling you to set such-and-such trimmer to (for example) 3:00. It just doesn’t work that way. Your question has no answer the way you’re asking it. I hope you can understand this.

And okay on the 226. I’ve said my peace. Tape can go sticky, even when brand new sealed in the package, and Scotch 226 is notorious for going sticky…it was one of the first tapes to exhibit sticky shed. You’ve been forewarned.

You came here seeking advice, and you’ve received it twice now. You now get to decide if you’re going to take heed.

Good luck.

 

[athuai]

Ok
Thanks for your time & info
Take care

 

[RRuskin]

...And okay on the 226. I’ve said my peace. Tape can go sticky, even when brand new sealed in the package, and Scotch 226 is notorious for going sticky…it was one of the first tapes to exhibit sticky shed. You’ve been forewarned...



Good luck.

Not only that but 226 sounds horrible.

 

[athuai]

Please re-read my last post. The trimmers would not have been set according to some physical position standard. They would be set according to what is dictated by the procedures in the calibration section of the service manual using the required test equipment. This would vary from machine to machine when new. You can take any calibrated tape machine old or new and compare it to another of the same model a none of the trimmers will be the same. There might be similarities, but enough variation that it’s not wise to try and extrapolate “correct” trimmer settings based on somebody telling you to set such-and-such trimmer to (for example) 3:00. It just doesn’t work that way. Your question has no answer the way you’re asking it. I hope you can understand this.

And okay on the 226. I’ve said my peace. Tape can go sticky, even when brand new sealed in the package, and Scotch 226 is notorious for going sticky…it was one of the first tapes to exhibit sticky shed. You’ve been forewarned.

You came here seeking advice, and you’ve received it twice now. You now get to decide if you’re going to take heed.

Good luck.

Thanks again, Sweetbeats!
You were right:
•sealed 226 tape was unusable
•I got MRL tape & learning/doing proper calibration
•I’m trying new RTM 911 tape
Thanks & Peace

 

[ecc83]

Re "trimmers"...heed Sweetbeats very well people!
This idea that the position of a trimmer (or volume or tone pot) has some specific effect on the signal levels, control levels or power outputs of equipment seems to be common and is TOTAL BOLLOCKS!

Just one example of why in this case of a bias control, trimmers, like all electrical components have both electrical and mechanical tolerances. These days such trimmers might be + or - 10% of nominal value. Ancient tape machines might have used 20% components.

Thus, the voltage coming out of a pot is not exactly determined except by careful measurement and is certainly not precisely related to the indication. Been some time since I biased up a tape deck but I recall the adjustment being quite critical in some cases? Turning the trimmer just a gnat's knacker can be "right" or "wrong". The correct setting was definitely NOT visibly different from the "off song" setting.
The same applies to setting the bias on a valve or indeed transistor amplifier...you MEASURE to get the current right. not set a pot "there"!

The joke in the film about "Look! This one goes up to eleven!" is just that. A joke...means FA.

Grounding: Yup, complex subject that need on site, bespoke solutions and a very systematic approach in solving problems.

In UK the rules for Earthing equipment are very strict. The earth wire must go to chassis and be secured by a bolt and star washer and nut (or nylok nut I think?) and said bolt must NOT do anything else, i.e. NOT secure a transformer.

Dave.