11-04-2017, 08:21 AM
Should the turntable on these be secured with a circlip? The parts list shows 'Turntable Clip' with a long obsolete part number, but there's no clip on the one I'm currently servicing.
Garrard TA/Mark II (4SP) - problems with stylus pressure adjustment
|
11-04-2017, 08:21 AM
Should the turntable on these be secured with a circlip? The parts list shows 'Turntable Clip' with a long obsolete part number, but there's no clip on the one I'm currently servicing.
11-04-2017, 10:18 AM
The TA and TB have a circlip to stop the turntable falling off when a portable record player is being carried.
Not sure about the 4HF. That's more of a transcription turntable and they don't normally need a circlip because they're not regarded as portable. Martin
BVWS Member
11-04-2017, 10:43 AM
Maybe I incorrectly quoted '4HF'. The deck is in a Bush SRP30C, which is in my workshop, and perhaps I misread the number on the deck chassis. The service data I have calls it a TA/MK II. I'll look for a suitable circlip anyway!
11-04-2017, 06:44 PM
The deck is actually a 4SP, not 4HF (apologies for the error), and runs quite well apart from a slight 'bumping' noise, which is almost certainly due to the idler wheel. I've now found a circlip which is a bit of a tight fit, so may look for a more suitable one. In the meantime, having found that, in the past, someone had fitted what appears to be a version of those Chinese Ceranic cartidges to the detachable headshell, by gluing it inside the fixing bracket from a BSR Turnover cartridge, leaving the t/o knob and 'flag' in place. So far so good. The deck can, and does play both mono & stereo records OK, but two things are puzzling. One is that the BUSH SRP30C in which this deck is used has an output socket for stereo. The pickup is wired so that the RH channel signal goes to the internal amplifier, and the LH sig. to the 'Stereo' socket, which looks like a 75 ohm TV aerial socket (it's original, Btw). The replacement cartridge had it's LH Channel + terminal wired to the internal amp., and LH - to the stereo socket, with no common return wire in the detachable head. Funnily enough it played OK that way, but I've rewired it so that the -ve terminals of the two channels are connected to common neg. The other thing is that, no matter how I adjust the set screw at the rear of the arm, I cannot get a tracking weigh reading at all on my trusty Garrard SPG pressure gauge, which I've checked with it's supplied 5gram test weight. The PU as described has been tracking record alright, but I dread to think at what stylus pressure. The headshell with cartridge, etc., as described weighs about 56G, which may be lighter than with the original Garrard Cartridge. Any suggestions as to how to remedy the tracking weight problem are welcome. Those Chinese Cartridges track at about 2-4 g, IIRC.
11-04-2017, 08:57 PM
(This post was last modified: 11-04-2017, 08:58 PM by Old Sparky.)
Perhaps the thread title should be changed to 'Garrard TA/Mark II (4SP) Problems with Stylus pressure adjustment' to avoid confusion.
13-04-2017, 07:57 AM
I've now managed to get the stylus pressure down to 10g., but how to access the underside of the PU arm, to check for faults in the SP adjustment (stretched spring, etc., I know not without removing the arm from the deck. It's shape will not allow it to be lifted up high enough to see what is at the hinge end, never mind repair or replace any parts there.
13-04-2017, 06:54 PM
I should add that I've now found out that the tension spring, mounted vertically at the rear end of the PU arm, needs to be stretched more in order to reduced the tracking weight. By turning the adjusting screw anticlockwise I've been able to reduce the SP to 3.5g, so that problem is solved!
|
Users browsing this thread: |
2 Guest(s) |