I managed a Pro Sound Store for over 20 years (from the late 70s to the early years of this century). I took notes of people bringing in turntables The Technics SL-BD10, SL-BD20, and SL-BD30 are turntables that customers ordered and stocked (while they were current models) and that customers brought in for belts. A few months before these models hit the shelves, Technics/Panasonic discontinued making turntables. The audio world was shocked, I even documented to the Panasonic sales reps and their supervisors that my store was selling a turntable with each system that our customers purchased. Everyone still had LPs, and everyone still needed a way to play their old vinyl. After about 4 months we were told that they had realized their mistake and began making these new models. I still remember getting these (at that time) new models in. This was an exciting time. These models do not take the same belt as their predecessors (most SL-B models use a different belt!). 

A few years later, there was an early, non-Panasonic, parts cross-reference with a lot of errors in it, and the info it contained had a belt that contradicts what Panasonic told me when I called to order parts direct, so I know my info is correct. There are many, many major parts dealers that copied the errors in the non-Panasonic parts cross-reference, and even that information was copied as if it was factual. Many major parts places are selling the wrong belts for these specific models, even to this day.

Here is the info I copied from my notes from inventory and my actual customer’s SL-BD10, SL-BD20, and SL-BD30 turntables:

These models are basically the same drive system, the differences in these models seem to be features. 

The SL-BD10 is a fully manual belt drive turntables. Most of the controls are on the outside of the dust cover. On the far left is the speed selector, it has 3 positions: On the left is a speed selector, 33 on the left side and 45 is on the right. There is no pitch control. If you have pitch issues with this model, there is a solution available, the process takes about a day, I can guide you through. Click contact seller near where it says turntables, etc. (upper right side of this page), I want to help. The next control to the right is a cue control. Move the cue control to where it shows up (arrow), and the arm raises, move it down and the arm lowers. Near the tonearm, toward the back is an anti-skating device. If you are having issues with your anti-skating device, click contact seller near where it says turntables, etc. (upper right side of this page), I want to help. The switch on the far right is an on/off switch. As it is a fully manual turntable, the user must move the arm to the record and either set it on the vinyl, or lower it with the cue lever. The plater does not begin spinning until the user hits the power on/off switch. When the user chooses, the user must raise the arm to stop playing the record. There is no automatic cut off, there is no auto-lift.

The SL-BD20 is a semi-automatic belt drive turntable. Most of the controls are on the outside of the dust cover. On the far left is the speed selector, it has 2 positions: left is 33 and 45 is on the right. There is no pitch control. If you have pitch issues with this model, there is a solution available, the process takes about a day, I can guide you through. Click contact seller near where it says turntables, etc. (upper right side of this page), I want to help. The next control to the right is a cue control. Move the cue control to where it shows up (arrow), and the arm raises, move it down and the arm lowers. Near the tonearm, toward the back is an anti-skating device. If you are having issues with your anti-skating device, click contact seller near where it says turntables, etc. (upper right side of this page), I want to help. The switch on the far right is an on/off switch. As it is a semi-automatic turntable, the user must move the arm to the record and either set it on the vinyl, or lower it with the cue lever. The plater begins spinning as the arm nears the platter. When the user chooses, the user may raise the arm to stop playing the record or hit the stop button. There is an automatic cut off at the end of the record.

The SL-BD30 is a fully automatic belt drive turntable. On the left is a speed selector, 33 on the left side and 45 is on the right. There is no pitch control. If you have pitch issues with this model, there is a solution available, the process takes about a day, I can guide you through. Click contact seller near where it says turntables, etc. (upper right side of this page), I want to help. The next control to the right is a cue control. Move the cue control to where it shows up (arrow), and the arm raises, move it down and the arm lowers. Near the tonearm, toward the back is an anti-skating device. If you are having issues with your anti-skating device, click contact seller near where it says turntables, etc. (upper right side of this page), I want to help. The switch on the far right is an on/off switch. As it is a fully automatic turntable, the user may move the arm to the record and either set it on the vinyl, or press the start/stop button. The plater begins spinning when the arm nears the platter. When the user chooses, the user must raise the arm to stop playing the record, or hit the start stop button. There is an automatic cut off when the record is finished playing.

Caution: I strongly recommend against using the repeat button. I read in a Stereo Review or something that the tip of the stylus is extremely hot while playing vinyl (I think it said thousands of degrees? unsure of the details), and that if the vinyl can cool properly, the damage is minimal. This source said it takes vinyl an hour to cool before replaying, or the damage is extensive. I had physics in college, and personally, I thought I was reading a bunch of %$&#*!. At that time I had become a manual turntable guy, but before that, I owned a semi-automatic, and before that I owned a fully automatic. When I went back to those records I bought with the fully automatic, I could easily hear that the vinyl was far worse on those records, and everything I bought after switching to semi-automatic was in great shape. It was the repeat button, I used it a lot when I had the fully automatic table. Please use the repeat button cautiously, or don't use it!

(SL-BD30 continued...) To the right of the repeat switch is a switch for the user to select the size of the vinyl (7", like most 45s, 10" or 12", like most LPs). There is a cue lever to the right of the tonearm (near the back). Move the cue lever up, and the arm raises, move it down and the arm lowers. Near the cue lever is an anti-skating device. If you are having issues with your anti-skating device, click contact seller near where it says turntables, etc. (upper right side of this page), I want to help. The switch on the far right is says "start stop". As it is a fully automatic turntable, the user can press the start stop button to begin playing a record, or move the arm to the record and either set it on the vinyl, or lower it with the cue lever. The plater begins spinning as the arm nears the vinyl. When the user chooses to stop playing the record, the user hits "start stop" to stop playing the record. There is an automatic cut off after the end of the record, the arm lifts and returns home.