RE: Precision E-200-C -
Radioroslyn - 11-24-2016
(11-24-2016, 09:34 AM)Mondial Wrote: Thanks, the video really explains everything. I just ordered one.
I don't know how they can build and ship this counter to the US for $9 and change?
Terry, do you ever operate 40 meter sideband? I just finished restoring a Kenwood TS-420 Hybrid and finally got back on the air recently with a random longwire antenna. Maybe we can work you one day?
Mike WA2YGA
>I don't know how they can build and ship this counter to the US for $9 and change?
Me either??? I wasn't paying attention where I ordered mine and I got the 2 of the higher fq models so they only go down to 1mc. Having thought about it I should have gotten the one that goes up to 65mc and down to like 10kc or so. I found some coil for the HRO the G and H coils. Lowfer anyone??
Could also be a good tool to align the lo and check tracking so you don't align the lo on the low side rather than the high.
>a Kenwood TS-420 Hybrid >
New one on me?? 520 and 530 I've heard of.
> do you ever operate 40 meter sideband?
Well I have a crappy 80mtr ant up and a built in tuner in the TS-440. Have been thinking about hanging a 40mtr V off the chimney, found a good price on some steel TV mast. Have been using pvc pipe but it kinda wonky can't stand up straight with guy wires (like me). Steel is much lighter and better choice I think.
> Maybe we can work you one day?
Sounds look a good time! I'm around most of the time so I'm at your disposal. Just let me know when and where.
de N3GTE
RE: Precision E-200-C -
Mike L - 11-26-2016
Gathering part information before I start on my Precision E-200-C. I have the later 1957-ish version. Like Bradley I was a little confused on the electrolytic cap polarity. They are C108a, b, c; shown on the schematic. After looking at this I believe that all three have the negative point connected to the center tap of the transformer. The positive of C108b and C108c is on each side of R111 and the positive of C108a is connected to chassis ground via the AVC+ jack. Am I correct?
Another Item I question is the line filter / choke. Should I replace the caps there as well? They are appear to be ceramic disc. There are 4 of them one appears to be a dual section (?) and 2 are hidden by the first line chokes.
RE: Precision E-200-C -
Mike L - 12-24-2016
Making progress on the E-200-C. I had a broken RF selector switch which is why I had no real output. Fixed that and continued to replace bad out of tolerance resistors and wax caps. Now I ran into a problem of my own doing. Replaced the old resistors under the 6AU6 tube, but to do so I had to disconnect several points. I thought I had good photos of all areas but I neglected one and that connection has me stumped. It is a bare wire lead from the lowest wafer in the stack located between band coils B and C. This lead runs up through the next two wafers and connects somewhere in the tube socket area. I just cant determine where. Anyone have theirs open that can send me a photo?
RE: Precision E-200-C -
Radioroslyn - 12-24-2016
I've got Sam's 200C apart it's a bit newer but looks like your wire goes to pin 7 of the 6AU6. This one has the osc tube mounted under the tuning cap not on the back of the BS. Be careful as there are things that look like resistors that have too many color bands they are rf chokes. Double check with the diagram.
RE: Precision E-200-C -
Mike L - 12-24-2016
The pinout for this tube has me a little confused. From a
TOP view would pin 7 be the first pin clockwise from the blank space?
RE: Precision E-200-C -
Radioroslyn - 12-24-2016
(12-24-2016, 04:49 PM)Mike L Wrote: The pinout for this tube has me a little confused. From a TOP view would pin 7 be the first pin clockwise from the blank space?
Yes.
RE: Precision E-200-C -
Mike L - 12-31-2016
Thanks again Terry. It seems to be "functional" although the band calibration is off. I'll address that later. The RF controls were very scratchy, at least RF-1 was. Spray cleaner didn't work so I removed them to open them up for inspection. RF-1 pot is defiantly bad, the other cleaned up but here is the problem. RF-1 is marked with 20000 (assuming 20k) RF-2 is clearly marked and measures as 25,000 ohms. The problem is the schematic shows both of these controls as being 200 ohm! Why would there be such a huge difference. They physically and brand are not the same so it is safe to assume they were replacements. So do I put 200 ohm or 20k ohm pots back in? Both are carbon wiper, but audio or linear taper. How is that determined?
RE: Precision E-200-C -
Radioroslyn - 12-31-2016
(12-31-2016, 08:33 AM)Mike L Wrote: Thanks again Terry. It seems to be "functional" although the band calibration is off. I'll address that later. The RF controls were very scratchy, at least RF-1 was. Spray cleaner didn't work so I removed them to open them up for inspection. RF-1 pot is defiantly bad, the other cleaned up but here is the problem. RF-1 is marked with 20000 (assuming 20k) RF-2 is clearly marked and measures as 25,000 ohms. The problem is the schematic shows both of these controls as being 200 ohm! Why would there be such a huge difference. They physically and brand are not the same so it is safe to assume they were replacements. So do I put 200 ohm or 20k ohm pots back in? Both are carbon wiper, but audio or linear taper. How is that determined?
I would go with the values listed on the schematic. You probably want linear tapper. Audio tapper would give you not much level change it the last half of the rotation. Must use carbon not ww pot. WW looks like an inductor to the signal.
RE: Precision E-200-C -
Mike L - 01-01-2017
Looking for a source now. I have an email out to Mark Oppat at Old Radio Parts. Hopefully he has something.
RE: Precision E-200-C -
JLuke - 07-27-2024
Hi All,
I have an E-200-C Signal Generator. The V10 and V11 assemblies are broken. Any ideas on replacement assemblies? There are 2 variable resistors mounted on each other with the shaft turning both pots.
Regards
Jim Vinton
jamesvinton@comcast.net
RE: Precision E-200-C -
DaleHCook - 07-28-2024
JLuke Wrote:I have an E-200-C Signal Generator. The V10 and V11 assemblies are broken. Any ideas on replacement assemblies?
Dual ganged potentiometers are not uncommon, but finding a 200 ohm dual gang will likely be difficult at best. The smallest dual gang I recall seeing new in recent years is 1k. Yours may have been custom made for Precision. Is there a part number, manufacturer, or other marking on your dual gang?
RE: Precision E-200-C -
RodB - 07-28-2024
Mouser has a 500 ohm dual gang pot but it may not physically fit your sig. gen.