On Sat, 18 Feb 2017 05:12:23 -0500, "Michael A. Terrell"
wrote:

wrote:
I picked up an old tube type Eico 320 Signal Generator. I'm tracing it
and checking stuff. There was a disconnected paper (.5mf 450V)
capacitor. The tube filaments and pilot light work. There is B+
voltage, The voltage from the 6X5 tube at the filter cap, is around
140VDC. (That seems low). The AC volts on the transformer secondary is
about 450V (or 225V each side of the center tap). There is a 2watt 5000
ohm resistor which comes from the power supply, which feels warm, so
apparently there is a voltage draw.

Anyhow, I have found three schematics in PDF format, an one as a .GIF.
They are probably all from the same source, and are very hard to read.
The parts symbols are ok, but where it says the cap and resistor numbers
(such as is that C8, C6 or C3), I can not make out the numbers. They are
blurry. I've tried several pairs of reading glasses, enlarge and shrunk
the diagrams on my screen, and they are just plain poorly scanned.

Does anyone have a decent schematic? And one that shows the voltages at
the tube contacts would greatly help too.

I intend to recap this thing, but first I need a useable schematic.


Are you looking at it in your browser, or a PDF reader? A lot of PDF
files look like crap in a browser, but they are fine in a real PDF program.

PDF - XChange Viewer. Version 2.5. Works in Windows 98se, which is the
OS I use.

I have other schematics, even some for other Eico stuff. Those are in
PDF and can be read. This one for the 320, was written to small to start
with and the scan is lousy too. I downloaded a few more PDF versions
sonce my post. They are all identical, just have different file names.
The GIF version is also lousy and looks the same as the PDF.

By the way, I downloaded that DJVU reader. I wont install in Win98se.
Considering the file size, I'd think the DJVU files are worse quality
anyhow. There has to be a lot of loss of detail to compress a file that
small.

Using Paint Shop Pro, I tried some filters and made size changes to the
GIF version. I saved it as a high quality BMP, but with no luck. I guess
a person cant fix what was lousy quality to begin with. At this point,
all I can do is spend hours trying to determine which parts are which,
and modifying the schematic in my paint software with BIGGER numbers.

That still wont tell me the correct voltages though.

I was evn willing to pay for a Sams Photofact, but it looks like they
dont have this one.