Technics SL-BL3 Linear TT Part ID

[jsmiddleton4]

I am working on a Technics SL-BL3. Nice turntable actually. I’ve got it sorted, plays fine. Needed some stuff and the necessary adjustments for linears, offset, servos, etc. I can not identify the white plastic screw with the spring attached which also means I have no idea what it adjust if anything and if it does how to adjust it.

I saw a sled for a QL-5 on eBAY. Has the same identical sled assembly with same white plastic screw/spring.

I down loaded its service manual but no luck with additional information so no identification.

Any help is appreciated.

 

[lini]

I have no idea what it adjust if anything and if it does how to adjust it.

Spring force adjustment for the dynamically balanced arm, I'd think. Because to me it would seem to be at exactly the same place, where the tracking force fine-adjustment screw is on the models, that still officially sport that (like for example the SL-5 and SL-DL5...) - just on the opposite side (i.e. on the top rather than on the bottom side).

Did you already have a look, what's on the opposite side in case of the SL-BL3?

Greetings from Munich!

Manfred / lini

 

[jsmiddleton4]

Thanks Manfred. There’s no hole as if an adjustment access on the bottom. It does have a weight that can be moved in and out a little to change VTF. Gotta take the dust cover off, tip the tone arm down which lifts the screw which is at the back of the weight up like a see saw. What’s crazy is nothing in any of the owner’s manual or service manual.

 

[jsmiddleton4]

I kept digging and it is a fine tune adjustment for VTF. Other Technics linears with same tone arm setup there’s an identifying sticker right next to that hole which is on the bottom of the sled assembly.

 

[jsmiddleton4]

This is a SL-DL1. Even can see the “+” and “-“.

 

[lini]

I kept digging and it is a fine tune adjustment for VTF. (...)

Yup, as already hinted to above, initially the tracking force fine-adjustment was a standard feature, which all of the models down to the SL-3 sported - and which can also be found in the corresponding user manuals and also in the service manuals (typically in the section "LOCATION OF CONTROLS"). But in later model generations that feature vanished.

So that's quite similar to the tracking force and antiskating (fine-)adjustment capabilities of the T4P radial trackers, initially sported by all of the models down to the entry-level SL-B10. In case of the radial trackers later model generations in the regular slim-line range would first lose the antiskating fine adjustment, which only the highest-ranking and more substantial SL-QX200 & -QX300 would still sport - whereas the tracking force fine-adjustment more slowly turned into a feature for the higher-ranking models, until it became a top-of-the-line-only feature of the SL-QD22 & -QD33 in the final generation.

In contrast to that, the higher range models, namely the T4P-armed variants of the SL-M1 and SL-M2 as well as the SL-MA1 would sport both (fine-)adjustments - whereas (fun fact!) the highest-ranking Technics T4P table of all, namely the SL-1000MK3D, would sport neither and hence ideally be used with 100%-T4P-compliant cartridges for optimal performance.

Anyway, I can only speculate, why that tracking force (fine-)adjustment wasn't covered at all in the service manuals for those later linear-tracking models - but I'd guess, that it was considered a once- and at-factory-only adjustment, as a readjustment would probably only be required, if one would completely disassemble the tonearm assembly.

Greetings from Munich!

Manfred / lini