Martin Mac 500

[RobbyBobby]

I am aware that the original Martin Mac500’s are getting old now but they are still knocking about in theatres and clubs.

Indeed I own several of them hence this post.

 

One of my Mac500,s after coming out of storage for two years had developed several faults.

Most of these faults related to connectors on the ends of the wire looms, which after many hours of multimeter testing and wire changing are solved - phew!

The bend in the metal crimped connector seems to snap off creating open circuit sockets everywhere! (The row of connectors going to the motherboard)

 

However…I am left with one problem which I am unable to locate.

Pan does not function!

 

At switch on, there is a small pause which is normal then the stepper motors ‘lock’ and ‘reset’ starts but the pan function is not doing anything.

When powered off versus on, there does appear to be a very slight difference of ‘resistance to movement’ change if you push the pan by hand pan indicating perhaps driver IC fail - but alas no!

 

I swopped the pan and tilt connectors over at the mother board, now tilt does not work and pan does, so the fault seems to be on the motherboard.

I have swopped the pan and tilt driver IC’s (PBL3772) and this indicates the fault is still on the motherboard.

 

Unfortunately, Martin does not seem to have a UK service centre anymore which is a great shame as they have been able to assist me in the past.

Is there anyone who has had a similar problem with pan not functioning?

 

One last thing. If the reset goes through its cycle and the pan is moved by hand so the limit switch is activated, the unit completes the reset and indicates there is feedback error (Fber).

I have cleaned the pan optical sensors, although I wouldn’t have thought that these would have caused this fault of pan not working!

Other than pan not working, the light does everything else very nicely.

 

I appreciate any help, assistance and guidance you may be able to offer.

 

Thank you in advance. I will let you know how I get on.

 

Rob.

[JohnMac]

Hi Rob,

 

It could be resistors associated with the "Driver" Chip. Try typing "MAC 500 tilt" in the search engine (top right of screen).

Historically it's been a common issue, and many members of the Blue room have contributed their knowledge and experience to this and other problems with the lantern.

 

Kind Regards

 

John Mac.

[RobbyBobby]

Thank you for that.

I have ordered some surface mount resistors.

I will let you know how I get on.

Thanks again.

Rob