Starman2007
Newly Enlightened
- Joined
- Sep 27, 2007
- Messages
- 1
Hello All
Im new to the forums so forgive me if i make any mystakes in my first couple of posts.
i have an Astroaimer II from Hutech ( www.hutechusa.com/astro-aimer.html )
I have had it for a year now and it is a great product for pointing out stars and constallations at night , but does have one flaw. when it is chilly or cold it will only light with a very din beam. The friendly people at Hutech said this was normal but that i could ship it back and they would try to adjust it for better performance at low temps. i did not want to do this for a number of reasons...mainly the hassel of getting it back and forth through customs.
ive read much in the forums about "pot mods" and "crystal alignment" and wanted to give it a go myself. I have dissasembled the unit (definitely NOT easy) there is a pot to adjust and while hooked up to an ampmeter (showing initally 240ma at room temp) i tweeked the pot but i did not seem to have any effect unless it was turned full clockwise at which point the beam got brighter and then very dim (reading around 260ma). turning the pot back restored nomal operation and brightness.
When i chilled the moduls the current rose to about 300 to 320ma and the beam got very dim.
i tried rotating the crystal assembly relative to the diode while chilled and the best operation seemed to be very close to the origional crystal position.
The crystal seems to be "glued " in its holder with a blob of white silicon rubber....i did not try to remove the crystal but only rotated it threaded assembly.
Question 1 -- what else can i do to improve the low temp performance?
Question 2 -- why would they have put the photo diode external (where it is measuring the GREEN output) instead of right after the IR diode where it would measure the actual diode IR output ??
Question 3 -- would a resistor mod be advisable in light of the photo diode in the circuit and what resistor would i try changing. The module circuit board looks SIMILAR but not exactly like some of the ones i have seen in the forums
I should state that i am an electronics technician and have experience tinkering with and building small electronic circuits.
The module has an IR filter placed at a 45% angle (used to feed an external photo diode) i will try to post pics later
thanks
Im new to the forums so forgive me if i make any mystakes in my first couple of posts.
i have an Astroaimer II from Hutech ( www.hutechusa.com/astro-aimer.html )
I have had it for a year now and it is a great product for pointing out stars and constallations at night , but does have one flaw. when it is chilly or cold it will only light with a very din beam. The friendly people at Hutech said this was normal but that i could ship it back and they would try to adjust it for better performance at low temps. i did not want to do this for a number of reasons...mainly the hassel of getting it back and forth through customs.
ive read much in the forums about "pot mods" and "crystal alignment" and wanted to give it a go myself. I have dissasembled the unit (definitely NOT easy) there is a pot to adjust and while hooked up to an ampmeter (showing initally 240ma at room temp) i tweeked the pot but i did not seem to have any effect unless it was turned full clockwise at which point the beam got brighter and then very dim (reading around 260ma). turning the pot back restored nomal operation and brightness.
When i chilled the moduls the current rose to about 300 to 320ma and the beam got very dim.
i tried rotating the crystal assembly relative to the diode while chilled and the best operation seemed to be very close to the origional crystal position.
The crystal seems to be "glued " in its holder with a blob of white silicon rubber....i did not try to remove the crystal but only rotated it threaded assembly.
Question 1 -- what else can i do to improve the low temp performance?
Question 2 -- why would they have put the photo diode external (where it is measuring the GREEN output) instead of right after the IR diode where it would measure the actual diode IR output ??
Question 3 -- would a resistor mod be advisable in light of the photo diode in the circuit and what resistor would i try changing. The module circuit board looks SIMILAR but not exactly like some of the ones i have seen in the forums
I should state that i am an electronics technician and have experience tinkering with and building small electronic circuits.
The module has an IR filter placed at a 45% angle (used to feed an external photo diode) i will try to post pics later
thanks
