Hello Everybody. I got a question regarding the clutch mechanism of the JVC PC100, which seem to cause the problem of fluctuating band speed. Pls. let me just insert a photo from the audiotechnika-blog for those, who cannot recall what a PC100 is [GALLERY=media, 387]Jvc Pc 100 From Audiotechnika Blog Cz by mariaan posted Jan 25, 2017 at 4:14 PM[/GALLERY] The tape speed fluctuation is clearly visible from the image below: playback of a constant beep recorded by a TCD5. the image shows the same recording, same tape played on the Sony TCD5 (right halve) and the JVC-PC100 (left halve of the photo). [GALLERY=media, 390]2500Hz SonyTCD5 Vs JVC_pc100 by mariaan posted Jan 25, 2017 at 4:14 PM[/GALLERY] You clearly see the effect of the smeared 2500Hz line in case of the JVC Now, I am afraid, the whole rpm-fluctuation is caused by the clutch of the JVC, which seems to be not only a complicated, 4-part thing, but the whole clutch seem to be under huge pressure all the time, when assmbled. Why I think so? Because the spring is compressed to its limits... and because the tiny bottom part has a much wider hole as the top 2 gears, which - i believe- lets the bottom mini gear tilt to sides as the clutch turns. [GALLERY=media, 388]Jvc Pc100 Clutch 1 by mariaan posted Jan 25, 2017 at 4:14 PM[/GALLERY] [GALLERY=media, 389]Jvc Pc100 Clutch 2 by mariaan posted Jan 25, 2017 at 4:14 PM[/GALLERY] Now the questions come: - is this problem known? and if yes, what is the proposed solution to fix the rpm problem? - do you think that this clutch is only for FFwd and FRwd finctions, and could be simply closed? the reason I am asking this is because there seem to be a second clutch just above the disassembled clutch on the foto. If the other clutch is really a clutch (I did not touched it yet), then the 1st one might really serve only for fast rwd and fwd. thanks in advance for all the comments! i am really looking forward to have constant tape speed on this beauty.
