Fun with failure

[kugelblitz]

So, it's been about half a year since i got a small lathe, and the first acceptably sounding record is still to pop up.
This last couple weeks i've been on an offensive to get the whole thing to work better.

Made the machine look a little more like frankenstein

DSC01588.JPG

DSC01587.JPG

First action was to get a brand spanking new needle from epos, sure looks better then the rusty old stock one then i had.
Second action was to make the pitch screw turn independent from the platter, 'cause as it was it was probably going too slow (78 pitch screw turning directly from a platter turning at 33 1/3)
Third action was adding some counter-pression for the head, 'cause on my machine there was none, and on pictures of similar machines i spot a spring here and there

Then it was time for the test, and off course it was failure once again.
The main problem is too low levels.

Might be useful to mention I'm running the head with a power-amp and a home made audio transformer
I think the levels at the head are ok, i can at least do the trick where you put a cup on the head and audable music comes out that i saw on a youtube video by a guy that fixes head on this forum (i think) See attached video:

MAH01266 (1).m4v

What could be the reasons for my super-low volume on the records i'm cutting?
Any tips are more then welcome
Cause so far i've just been having fun with failure

[markrob]

Hi,

Maybe you are not getting enough drive voltage at the head. Since you mentioned a home made transformer, I am assuming you have a 500 ohm head. Try cutting one watt at 1Khz and see if it is reasonably loud. For a 500 ohm head, that would equate to about 22 VRMS at 1Khz. V = sqrt(power * head impedance). Measure this at the head terminals with an AC voltmeter. If you are not getting enough volume under these drive conditions, then I would suspect you head needs some servicing.

Mark

[kugelblitz]

Hey Mark,
you already helped me earlier with this transformer biznes , but i didn't heed your advice and took the diy-route.
I don't know how to "cut one watt at 1khz", do i need to have any special equipment for this, like a signal generator or such, or can i do it with appliances i have laying around the house?

[markrob]

Hi,

You need some sort of signal generator with an adjustable output level. If you own a smartphone, I'm sure there is a free app for that. You can also do the same on a PC using something like Audacity. You feed the generator (set for a 1Khz sine wave) into your power amp and adjust your output until you read the voltage required to produce 1 watt at the head terminals. For 500 ohm, that would be 22 Volts Ac RMS. Most any digital or analog meter will work fine for that. Since you don't seem to have electronics skills or equipment, I'm curious how you were able to fabricate a transformer and verify its operation?

Mark

[kugelblitz]

Well, i do know how to hold a soldering iron, and do have a multimeter
i did quite a bit of effects building in my days, but mainly recreating other people circuits or sticking together bits and pieces of different circuits with varying degrees of success.
the lingo is pretty foreign to me though

"verification" was just by the rise in volume at the level of the head after installation of the transformer, for which specs were provided by another user here who used the same head and made the same transformer...

[markrob]

Hi,

Given that, you should be go. Let us know what you find.

Mark