Bob Young said:
Has anyone retrofitted their Televue focuser with one of these FeatherTouch units?
I've installed two of them on my scopes. After seeing what TeleVue's Focus Mate looked like, I put myself on the waiting list for the first TVRFB's to be delivered. My first TVRFB went on my old TeleVue Genesis SDF (see attached photo) and it worked great, so I kept an eye out for a used one and grabbed the first one I saw on A-mart (another TVRFB) and installed it on my TV76. I considered putting one on my Pronto but since I only use it for Solar viewing, I saw no need.
Was wondering if it performed to expectations and how difficult it was to install.
They both perform flawlessly. The TVRF(B) have a 10:1 fine focus as opposed to the Focus Mate's 6:1 ratio. It takes a little careful adjustment to get them just right but it's not difficult. Some words of warning:
1. The original TV pinion block screws will be TIGHT. Also, the screw head sockets will be filled with black paint which must be scraped out first to ensure a good Allen wrench fit. To remove them, use a good quality US made Allen wrench of the proper size and grind the end of it flat to give a full depth hex shape which will bite into the screw head.
2. Upon removing the original TV pinion block and pinion shaft, DO NOT pull the focuser draw tube out of the focuser housing - you will never get it back in right. (This is a warning from David Nagler himself.)
3. Follow the TVRFB instructions carefully and you should have no problems. Installation took me about 45 minutes, being slow and careful.
How does it compare to the full FT focuser?
Dunno, never had one.
At $220 to $250 they seem a little pricey for what you get, but an easy bolt on upgrade beats replacing the whole focuser.
When you see and feel the quality of the TVRFB, you will know you got your money's worth. Also, I like the version with the brake screw as it enables you to vary the tension of the focuser easily for just the right feel.