Antenna Mast Dilemma

[Webmanic70]

I know the antenna mast has been covered in many threads but I have a question that is probably to simple to mention and I do not want to get it wrong because these things are irreplaceable. I want to know what stops the aerial mast when it is in the fully extended or retracted position. The end is connected to the drum using a splitpin, if the winder keeps going then would the plastic cord not snap or is it strong enough to stop the drum from turning?

Like most people my mast has snapped some time back on my 1970 240z. I pulled it from the car to replace the mast with an exact NOS replacement (on Ebay about 5 years ago if your wondering). The motor in the antenna is pristine, no dust or dirt and looks almost new. I removed the old broken mast and aerial. I have then threaded the new mast into the guide and around the drum, but the hole for the split pin which holds the end of the mast to the drum is in the wrong location from where I last stopped the winder. Therefore should I fully extend the aerial and simply connect the end where the splitpin is currently located and let the winder do the rest or wind it to a set location and then connect the mast? Hope this makes sense.

[tlorber]

On my car, which is a '73, there is a manual switch, so I have to hold it up until I want the antenna to stop, and then hold it down until I wan the antenna to stop. I'm not positive that was the stock configuration, but I believe it was. I have seen writeups here creating logic circuits that handle this automatically, but it is way more work than I have the time or inclination to deal with at this time.

[AZ-240z]

I have attemped to attach the pertinent pages from Wick Humble's book "How To Restore Your Datsun 240Z". Gleen what you can from these pages, but,

it is my opinion that the whole reel spool is driven by a worm gear connected to the antenna spool by gears and plates that act like a slip clutch.

When lubed and installed properly with the correct tension on that rather large spring on the center threaded spool post, the antenna mast should extend and retract to its physical limits protected by this slip clutch arrangement of plates and gears. As long as you don't incorrectly adjust, or change, that

springs tension, the mast should work as intended.

I did not stay at a Holiday Inn last night so please continue to do your own fact finding. Hope this information helps.

Dan

Original Owner, hls30-20419

[Webmanic70]

I am an idiot. I have that book in the library, it is exactly what I was looking for. Thanks Dan for the reminder and tHe thoughts on the slip clutch.

Edited July 3, 2012 by Webmanic70