Although I have been using a converted 16mm to run the GS1200 lamp for the last few years. I came across another slide projector Leitz Pradovit 253series that was being scrapped. The mechanics had given up working long ago, along with a burnt out lamp socket. I pulled it apart mainly for the transfomer. Its been a little project to make up another power supply just for the fun of it. The only thing I bought for it was a 15 amp illuminated rocker switch. Yesterday I finished it and compared the voltage output with the old B/H power supply.
To my surprise with a 24volt 250watt lamp running the voltage drop was more than I thought it would be on low 20VAC on high 21.5VAC. Although the Leitz Pradovit slide projector never had a choice of low and high, only high. I did find a lower tapping. Checking the voltage again this time with the transformer from the Leitz and with the 250watt lamp running I got 22VAC on the low and a 23.5VAC on the high, ah! that's better.
So now I have retired the old X B/H 16mm power supply with this one. I will run the Osram Xenophot ELC 24volt 250watt lamp at the 23.5VAC from now on and se how that works out.
To be honest I had forgotten about the voltage drop when the lamp was on, although the old B/H did show 24 volts without the lamp running I did not think it would drop that much, adding another 2 volts bringing it up to a running voltage of 23.5VAC should be bit brighter. A good test would be some Scope films
for home use this should be fine![Smile](https://8mmforum.film-tech.com/vbb/core/images/smilies/smile.png)
Glad to be at the end of projects both at the Historic Park and home, time to chill out![Smile](https://8mmforum.film-tech.com/vbb/core/images/smilies/smile.png)
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To my surprise with a 24volt 250watt lamp running the voltage drop was more than I thought it would be on low 20VAC on high 21.5VAC. Although the Leitz Pradovit slide projector never had a choice of low and high, only high. I did find a lower tapping. Checking the voltage again this time with the transformer from the Leitz and with the 250watt lamp running I got 22VAC on the low and a 23.5VAC on the high, ah! that's better.
So now I have retired the old X B/H 16mm power supply with this one. I will run the Osram Xenophot ELC 24volt 250watt lamp at the 23.5VAC from now on and se how that works out.
To be honest I had forgotten about the voltage drop when the lamp was on, although the old B/H did show 24 volts without the lamp running I did not think it would drop that much, adding another 2 volts bringing it up to a running voltage of 23.5VAC should be bit brighter. A good test would be some Scope films
![Wink](https://8mmforum.film-tech.com/vbb/core/images/smilies/wink.png)
![Smile](https://8mmforum.film-tech.com/vbb/core/images/smilies/smile.png)
Glad to be at the end of projects both at the Historic Park and home, time to chill out
![Smile](https://8mmforum.film-tech.com/vbb/core/images/smilies/smile.png)
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