Forum Replies Created
-
AuthorPosts
-
DillenModeratorNormally, these remote controls need very little attention.
Martin
DillenModeratorCheck for excess ripple on the supply voltages (bad filter capacitors).
If your CPU module has an electrolytic capacitor near the edge connectors, replace it.Martin
DillenModeratorIt’s an oil stop.
It prevents oil from the bearing creeping up the spindle to the pulley.Martin
DillenModeratorI would never increase the current limit of a fuse significantly.
Sometimes you can find 315mA fuses rather than 300mA. That would be OK.Martin
DillenModeratorJust a side note:
The 47uF axial capacitor on the subchassis must not rest on the black plastic support.
There is no room for that. The subchassis movement will be restricted by it when the Beogram is assembled.
It must be arranged like the original – down on to the metal.Martin
DillenModeratorThere are four holes provided for C24 (to allow for components with different pin spacing).
Going from C27 towards C29 they are negative, positive, positive, negative.
Note that the two negative holes are connected together through the jumper next to C1.
This can often cause confusion.Martin
DillenModeratorI am not aware of any modern replacements.
You could ask at Danish Sound Parts.Martin
DillenModeratorNothing missing or broken as far as I can tell.
The lit sliding pointer just leans against the rails, it doesn’t grip them.Martin
DillenModeratorIsolating the secondary merely means disconnecting everything on the secondary (load) side of the transformer.
Doing this will confirm that the humming is caused internally in the transformer and not as a result of a too high load.Replacing the transformer is the only cure.
Having siad that, the humming transformer will continue to work technially with no problems for many
years on, but of course the humming can be annoying.Martin
DillenModeratorIt can be difficult to spot the crack in the worm gear.
I have seen this several times, and I suggest you look again.
Or simply pull off the gear and glue it back on using a good 2-comp. epoxy.Martin
DillenModeratorLubricating the motor bearings is not that easy;
Clean out in acetone bath for 24 hours, slush around every now and then to flush as much dirt and dry oil remains out of the pores in the metal as possible.
Allow to airdry for a few hours.
Submerge in sinter oil containing the correct and required additives.
Pull vacuum until bubbling stops.
Release vaccum and leave bearings in the oil for a few hours to allow the oil to soak into the pores.-And if the bearings are already worn from running without proper lubrication, even for just a brief moment, they won’t
ever be any good again.Easier is to simply replace the bearings (read here):
https://www.dksoundparts.com/product/motor-bearings-set-for-beogram-motor-with-3mm-spindle/Martin
DillenModeratorReverse spinning at mains on could f.e. point to lack of input to the processor from the tacho-sensor.
The deck initiates the motor circuit by reversing it ever so slightly to see the feedback from the tacho sensor.
With no feedback, the reversing command will not stop.Could be a bad sensor-opto but is more likely to be a cracked solder joint somewhere – at the ribbon cable or at the CPU socket. In decks with the extra IC 4013 inside the CPu housing, this IC can also be at fault. A scope will tell.
Ripple on supply voltage(s) can also cause strage things. Did you replace all capacitors in the kit?Martin
DillenModeratorYou don’t state if your deck is a DC- or AC-motor version, but in general:
Dry motor bearings (if never replaced it’s time now).
Bad speed relay (if never replaced it’s time now).
Bad speed trimmers (if never replaced it’s time now).
Bad contact in speed fingerwheel-trimmers (clean them anyways).
Cracked solder joints at PCB connectors (later decks only), particularly the one for the speed dial panel.
Bad TVS diodes in motor (not that common but it does happen. AC-motors don’t have them).
Any combination of the above.Martin
DillenModeratorIt will not work.
The “old” and “new” datalink systems are not compatible.Martin
DillenModeratorYou can glue on wooden dovel pins instead. Paint them black afterwards.
Martin
DillenModeratorThe lamps are correct.
Weak rectifier would be my guess. Wouldn’t be a first.Martin
DillenModeratorCheck the fuses for the amplifier section. (F3/F4 I think).
Sounds strange, I know – but try it.Martin
DillenModeratorMeasuring with an ohm-meter (“DC-resistance”) will not give the impedance (“AC-resistance”).
It may come close, but don’t count on it.Martin
DillenModeratorAn IF stage slightly off correct alignment can cause this.
As pronounced as this, it could be the last stage before the detector.
Don’t attempt to do any alignment unless you have the proper instruments for it.
There are ways to do it without, but it usually requires more than average experience.I don’t think it does, but if your Beomaster uses AF116/AF117 transistors in the IF stages, one or more of them could also be bad (or just weak). AF125/AF126 are not as fault-prone.
Martin
12 August 2024 at 15:57 in reply to: beomaster 1000 ( type 2317 ) restoration & improvements? #58200DillenModeratorWhat, in your opinion, would be a better RIAA curve?
Martin
-
AuthorPosts