View Single Post
Old 8th Apr 2020, 6:05 pm   #18
ricard
Octode
 
ricard's Avatar
 
Join Date: Mar 2006
Location: Lund, Sweden
Posts: 1,631
Default Re: Tandberg model 15 bias adjustment

When I'm setting up the bias on these machines, I usually momentarily connect a 'scope to the recording head while turning the bias trimmers, not to see the absolute level, but to get an idea if I'm actually increasing or decreasing the bias.

If you have another recorder you can set them up side be side, and use the second one as a playback machine for the same tape, i.e. you place the tape on the left hand reel holder of the left machine (the one you want to set the bias on), thread it through both machines, and place the take-up reel on the right hand machine. Setting the second machine to playback you then get a three-head arrangement, albeit with a large distance between the record and playback heads!

One thing though, is that the right hand machine must run at exactly the same speed, or slightly faster, or there will be an ever increasing loop forming between the machines.
ricard is offline