positioning probs.

Bram

I have a Philips motor and a 180 cm antenna. I have a Nokia and a Philips positioner. Problem: If I mark the satellite as I find them the positioner misses when I go back.
E.g.: Astra is on 365 (position 6) I turn the antenna to watch another sat and then try to go back to 365. It seems like it is working OK, but now Astra is on e.g. 374 so I havve to manually reset the positioner.

Could it be that the wire for steering voltage is too thin??
I have the same problems with both positioners. (Not used at the same time)

2old4this

a bad pulse cable can cause noise spikes to be counted as motor pulses (or real motor pulses to be lost). So check your connections, and check that the cables are properly insulated; that there is no rusting/etc.
Might also be play in the motor/actuator itself due to wear&tear.

2old

Channel Hopper

From a previous life I was led to believe Philips actuators were Optical coupler type position control so only the wear and tear scenario fits the bill.

Philips (actually the Gregorian from Fibo) used a nylon cog which wears out quickly if the dish is able to hit a stationary object or rund over to the fixed mechanical limit about 60 degrees either side of centre. Some companies made a brass copy of the cog and sold it on at wallet depleting amounts. A local lathe operator may be able to make something up thats able to do the job

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There is a very fine line between "hobby" and "mental illness"

2old4this

my motor cog is also nylon. It's made in such a way that the cog itself is somehow glued onto a metal spindle. The dish is huge and heavy, and especially at the extremities of its travel, bears heavily on that glue connection. Eventually the glue gave out and it started to slip and all my stat positions were being screwed up. I solved the problem by drilling through the components that were glued, and inserting a metal pin in such a way that they could no longer move relative to each other.

2old

Channel Hopper

If only all problems in life were so easy

Im trying to shoehorn a 500cc engine into a 250 bike frame, just for kicks. Im losing the enthusiasm fast and the hacksaw is calling me from the corner of the garage to make the new crank a stressed member

Must resist !

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There is a very fine line between "hobby" and "mental illness"

Bram

Thanks both of you. I know it is nylon in the cogs. Tomorrow I will
have a peak inside. The slipping cogwheel might just be the thing.
I'll keep you posted.
By the by...
Would anyone know where I can get a manual for my Philips positioner. I only need to know how to save the diff. positions correctly

rolfw

Haave a look at this thread Bram and perhaps PM Jim, the postioner may have similar instructions. Philips D2MAC Receiver FOC

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