Does anyone know what the difference is between a Topcon AP-L1 and a Topcon AP-L1A?
From outward appearance, I can see that that the Horizontal and Vertical release are lever action as opposed to buttons. Are there any other differences?
Thanks,
The Bow Tie Surveyor
One worked and one did not . Apl1-a was the fix for the Apl1.. Apl1-a was bullet proof . Had 2 of them .
> Does anyone know what the difference is between a Topcon AP-L1 and a Topcon AP-L1A?
>
> From outward appearance, I can see that that the Horizontal and Vertical release are lever action as opposed to buttons. Are there any other differences?
>
> Thanks,
>
> The Bow Tie Surveyor
I do see from the AP-L1A manual that you could adjust the tracking sensitivity where with the AP-L1 you could not. The AP-L1A also had a laser shutter (whatever that did).
The AP-L1 is the older of the two models and preceded the AP-L1A.
The AP-L1 is rated 3" accuracy, the AP-L1A is rated 2" accuracy. They have many similarities. The previously noted release mechanism difference for the servo motors to be able to manually rotate the instrument and the scope is the most obvious physical difference.
When I came to work at Hayes in October of 1998, the AP-L1A was a current model, having superceded the by then discontinued AP-L1. Since they both predate my exposure to robotic instruments, I do not know the dates of their lifespan as new instrument models.
We sold a few AP-L1 units but quite a few AP-L1A models. Probably still have a couple of used ones in the back gathering dust.