8mm Forum: new worm gear installed, no sound

This is topic new worm gear installed, no sound in forum 16mm Forum at 8mm Forum.

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Posted by David Tavares jr. (Member # 2278) on December 01, 2010, 04:41 PM:

well installed new worm gear in bell & howell 1545b projector, timed and alighned everything by manual, film runs great quiet, steady and loop restorer works fine. heres my problem no sound at all no static when i turn knobs flicking a piece of film in front of sound drum and photocell still nothing, bought this projector on ebay with no powercord and i did work with out knowing if it ever worked. exiter lamp works fine. any help or suggestions on were to start will be a great help, thanks David

Posted by Jim Schrader (Member # 9) on December 01, 2010, 06:01 PM:

you can check the lens in front of the exciter bulb this has to be aligned just right.

Posted by David Tavares jr. (Member # 2278) on December 02, 2010, 01:26 PM:

Jim, i didn"t move or adjust anything on the sound head when i installed worm gear. with your suggestion i tryed to tweak the lens nothing happened, there is no static, when you turn exiter lamp on and turn volume knob you don"t even hear static like no power to amp.

Posted by Jeff Taylor (Member # 442) on December 02, 2010, 02:34 PM:

Try a non-sync input (mic/dvd player/etc) to see if the amp is dead or whether it's in the photocell input circuit. At least this will give you a starting point.

Posted by David Tavares jr. (Member # 2278) on December 03, 2010, 09:10 AM:

Jeff where exacly on the circut board would i hook up a mic to, would it be where the photocell connects to black, red, shield thats pin 1,2,3,or would it be somewhere else. i don't want to hook it up till i am exacly sure.it looks like this circut board might have been looked at before because the 3 silcone rectifiers look like someone took them out to test them. i am electrical smart but electronics dumb if you know what i mean. anybody on this forum test and repair circutboards.

Posted by Jeff Taylor (Member # 442) on December 03, 2010, 02:11 PM:

Doesn't your projector have a mic input jack accessable? I have a B&H similar to yours but it's so buiried I can't get to it to check. In any event, that's what I had in mind. If you have to start playing around on the board I'd be inclined to pass. There's a guy on 16mmfilmtalk named Ken Layton who's very sharp on B&H, or perhaps Rich Patchett will chime in here with more suggestions. Best of luck.

Posted by David Tavares jr. (Member # 2278) on December 03, 2010, 05:16 PM:

Jeff i only have a aux. speaker jack. thanks for your help, I think i am going to buy a pack of wire markers and unsolder this board and test every component on this board, anybody got a cheap board out their they want to get rid of. i won this projector off ebay for .99 cents it came with no power plug a cracked worm and a whole lot of dirt. i installed a new worm in it to learn how to do it for my other projectors, this baby runs better than my others except for sound so i realy like to get it going. so again thank you for all your help let you know how i made out. David

Posted by Jeff Taylor (Member # 442) on December 04, 2010, 09:44 AM:

Dumb question, but are you sure all of the leads including the speaker got reconnected when you finished the worm gear, and that the fuses are good? Since you had the machine totally apart that sounds like a possibility. If you're not even getting a "pop" when you turn it on it sounds like amp's not coming on which could obviously be a no power situation or a blown amp board, in which case you'll be looking for a donor machine. I'd start by tracing voltages and making sure it's got power, which was a major part of my suggestion to try a non-synch source. Good luck with your project.

Posted by David Tavares jr. (Member # 2278) on December 04, 2010, 10:38 AM:

Hi Jeff never a dumb question only a dumb answer. Jeff i tested the only fuse i could find and was good i am going to double check all wiring and try do adjust lens. Jeff thanks for taking the time to try to help me.

Posted by David Tavares jr. (Member # 2278) on December 04, 2010, 04:56 PM:

Jeff you put me in right direction, i bypassed speaker and tried another still nothing, so i checked aux jack with test speaker nothing, jumped aux. jack i have sound, installed projector speaker no sound. result speaker blown out and aux. jack rusted out i will search for new ones or used. Jeff and Jim thank you very much for all your help w/ this problem. David

Posted by Jeff Taylor (Member # 442) on December 05, 2010, 10:18 AM:

Back in the day that would have been nothing more than a trip to Radio Shack, but they don't seem to have much of anything in the way of electronic components anymore. Anyhow, I'm glad it was such a simple, if frustrating repair once you got on the right track. Frankly, though, I am a bit surprised that you had a blown speaker given the relatively low power of that amp, but if you've checked it that must be the case. Glad you figured it out after all the work of changing a worm gear!

Posted by Richard C Patchett (Member # 974) on December 05, 2010, 11:55 PM:

Greetings Dave
I should have a answer for your parts on Monday
RC

Posted by David Tavares jr. (Member # 2278) on December 06, 2010, 05:19 PM:

Richard e-mailed some pics of speaker and jack looking for similar items if i can get them, thanks David.

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