Forums :: NEW! Web Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives
Support This Site: Contributors :: Advertise


It is currently Dec Mon 06, 2021 12:39 am


All times are UTC [ DST ]





Post New Topic Post Reply  [ 213 posts ]  Go to page 1, 2, 3, 4, 5 ... 11  Next
Author Message
 Post subject: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Wed 17, 2020 2:10 am 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
Thinking of working on these next. I was only going to fix the "C" for myself, still going to keep the "C", but going to fix and sell off the E 200 if I can. Don't know the condition, they came from two different individuals. The "C" is the better of the two.

I did not know the difference between the two units, this helps having them side by side. The "C" unit has two additional bands - F2, & F4.

The case is slightly larger on the "C". The handle area of the top sheet metal is punched different for the handles. The newer unit has smoothed edges around where it was pressed. Also, there is a small hole punched in the top front of "C" with a plastic plug that E 200 does not have.

The newer unit "C" looks like someone been in the large tuned dial (whatever its called) hope it works. Maybe it was repaired at one time, the two caps dont look original.


Attachments:
P200&C_F.jpg
P200&C_F.jpg [ 524.54 KiB | Viewed 4421 times ]
File comment: E200 Left E200C Right
P200&C_coveroff.jpg
P200&C_coveroff.jpg [ 466.04 KiB | Viewed 4421 times ]
File comment: E200
P200_BL.jpg
P200_BL.jpg [ 660.23 KiB | Viewed 4421 times ]
File comment: E200C
P200C_BR.jpg
P200C_BR.jpg [ 684.35 KiB | Viewed 4421 times ]

_________________
only the dead fish go with the flow
Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Wed 17, 2020 3:53 am 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 5858
Location: Littleton, MA
You have some nice examples of Precision’s early signal generators. The E-200 is from just before World War II, and your E-200-C is from just after the war. It has the early square-cornered style case.

Here’s a little bit of their history:
viewtopic.php?f=8&t=363695

Here’s how I restored my E-200-C:
viewtopic.php?f=8&t=363692

_________________
Steve Byan https://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Wed 17, 2020 6:25 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
You have some nice examples of Precision’s early signal generators. The E-200 is from just before World War II, and your E-200-C is from just after the war. It has the early square-cornered style case.

Here’s a little bit of their history:
viewtopic.php?f=8&t=363695

Here’s how I restored my E-200-C:
viewtopic.php?f=8&t=363692


thank you that will help a lot. I am trying to understand what is needed to calibrate this unit? Not sure I have the tools to do this. I originally picked up that frequency counter kit to help calibrate this, not sure it is necessary.

Modulation adjustment, did you check yours? I have no way to test modulation levels I dont think.

_________________
only the dead fish go with the flow


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Wed 17, 2020 6:54 pm 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 5858
Location: Littleton, MA
ttx450cap wrote:
I am trying to understand what is needed to calibrate this unit? Not sure I have the tools to do this. I originally picked up that frequency counter kit to help calibrate this, not sure it is necessary.

A frequency counter is what you need to calibrate the frequency scale of the E-200's, but I would advise against doing it unless you've had to replace parts in the L-C tank circuit. Even then, I'd think twice. Just use the frequency counter to set the frequency instead of the dial, if you need that much accuracy.

ttx450cap wrote:
IModulation adjustment, did you check yours? I have no way to test modulation levels I dont think.

I don't recall any calibration adjustment, you just get what you get. I used a scope, but if you can hear the modulation on a radio, that's good enough.

_________________
Steve Byan https://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Wed 17, 2020 11:24 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
ttx450cap wrote:
I am trying to understand what is needed to calibrate this unit? Not sure I have the tools to do this. I originally picked up that frequency counter kit to help calibrate this, not sure it is necessary.

A frequency counter is what you need to calibrate the frequency scale of the E-200's, but I would advise against doing it unless you've had to replace parts in the L-C tank circuit. Even then, I'd think twice. Just use the frequency counter to set the frequency instead of the dial, if you need that much accuracy.

ttx450cap wrote:
IModulation adjustment, did you check yours? I have no way to test modulation levels I dont think.

I don't recall any calibration adjustment, you just get what you get. I used a scope, but if you can hear the modulation on a radio, that's good enough.


ok thanks

_________________
only the dead fish go with the flow


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Fri 19, 2020 4:09 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
You have some nice examples of Precision’s early signal generators. The E-200 is from just before World War II, and your E-200-C is from just after the war. It has the early square-cornered style case.

Here’s a little bit of their history:
viewtopic.php?f=8&t=363695

Here’s how I restored my E-200-C:
viewtopic.php?f=8&t=363692


I noticed you stayed with a 2 prong plug. I watched one video, believe it was the raidoguy he installed a 3 prong. Carlson video he wired his to a 2 wire, said he did not want any feeding back up through ground in case. leaning to a 2 prong polarized

_________________
only the dead fish go with the flow


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Fri 19, 2020 4:27 pm 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 5858
Location: Littleton, MA
ttx450cap wrote:
I noticed you stayed with a 2 prong plug. I watched one video, believe it was the raidoguy he installed a 3 prong. Carlson video he wired his to a 2 wire, said he did not want any feeding back up through ground in case. leaning to a 2 prong polarized

I disagree with Mr. Carlson. I don't think adding a three-wire line cord increases the RF leakage.

I didn't replace the line cord on my E-200-C because it was in good shape and I'm not overly concerned with the risk of an ungrounded case, although one must be alert to potentially dangerous situations. I always use an isolation transformer on any AC/DC sets – I wouldn't use the ungrounded case of the E-200-C to work on an AC/DC radio that was directly connected to the power line, even though it is possible to do this safely if you take the right precautions.

I usually connect my frequency counter to the E-200-C, so the coax shield from that ends up grounding the E-200-C chassis and case. It would be better to run a dedicated ground wire, as the ground path through the counter probably wouldn't survive a short to the hot side of the power line, or to use a three-wire cord.

Adding a three wire cord would have required enlarging the hole in the shield for the line filter and procuring a larger Heyco strain relief clip. I elected not to bother.

_________________
Steve Byan https://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Fri 19, 2020 6:15 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
ttx450cap wrote:
I noticed you stayed with a 2 prong plug. I watched one video, believe it was the raidoguy he installed a 3 prong. Carlson video he wired his to a 2 wire, said he did not want any feeding back up through ground in case. leaning to a 2 prong polarized

I disagree with Mr. Carlson. I don't think adding a three-wire line cord increases the RF leakage.

I didn't replace the line cord on my E-200-C because it was in good shape and I'm not overly concerned with the risk of an ungrounded case, although one must be alert to potentially dangerous situations. I always use an isolation transformer on any AC/DC sets – I wouldn't use the ungrounded case of the E-200-C to work on an AC/DC radio that was directly connected to the power line, even though it is possible to do this safely if you take the right precautions.

I usually connect my frequency counter to the E-200-C, so the coax shield from that ends up grounding the E-200-C chassis and case. It would be better to run a dedicated ground wire, as the ground path through the counter probably wouldn't survive a short to the hot side of the power line, or to use a three-wire cord.

Adding a three wire cord would have required enlarging the hole in the shield for the line filter and procuring a larger Heyco strain relief clip. I elected not to bother.


hum... not sure which direction I will go. I need to look at the case and look things over. I have not got a chance to read over the usage manual, but I noticed how they show all the test eq on a metal bench with common ground. I guess this help prevent ground loops. I need to go add a releaf to the CD unit to prevent the cord from winding up. Do you run all your test gear through a iso when using? thks Still learning here.....

Little disappointed in the "good" case cover on the e-200 c. It has more pitting in it then I realized. Hope it clean up decent.

_________________
only the dead fish go with the flow


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Fri 19, 2020 6:32 pm 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 5858
Location: Littleton, MA
ttx450cap wrote:
[hum... not sure which direction I will go. I need to look at the case and look things over. I have not got a chance to read over the usage manual, but I noticed how they show all the test eq on a metal bench with common ground. I guess this help prevent ground loops.

Actually, having each piece of equipment separately grounded in addition to the test lead ground creates ground loops. But for purposes of working on antique radios, you don't need to worry about ground loops through the test equipment. You won't be working with any signal level that is small enough for ground noise to matter.

ttx450cap wrote:
Do you run all your test gear through a iso when using?

No! Only the unit under test gets connected to the isolation transformer.

_________________
Steve Byan https://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sat 20, 2020 9:58 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
For what it's worth.. I had binding problems with the variable capacitor. Passing on here for the next person or can add to this.

Binding in bearings are usually caused by junk in the bearing , worn bearings, worn race, etc exceeding tolerances. Concerned about going in to deep, I stopped at totally taking it apart. If I have taken it apart I might have needed to purchase a new bearing, or worse. Might have to purchase roller bearing and bearings down the road...

The bearing/race in picture is a inexpensive lateral bearing. These can expand, not to mention the bearings surfaces.

Scope is to help assemble of the bearing unit, as it can cause a headache. This is the best I could come up with, this is my first attempt too.

Clean assembly, create a paper/plastic shim, I could not go past 2 turns with paper. As in pict, slide race housing down while bearing are in place. Slowly tight screws while pushing down on the plunger seating the bearing. You will feel the bearings seat, and make sure that the bearing outer housing is centered.

Hope this helps, I am sure there might be other procedures.

p.s. I did not want to fill it with sticky grease, so opt for dryer method


Attachments:
var_cap_balls1.jpg
var_cap_balls1.jpg [ 429.02 KiB | Viewed 4187 times ]
var_cap_balls1.2.jpg
var_cap_balls1.2.jpg [ 587.74 KiB | Viewed 4187 times ]

_________________
only the dead fish go with the flow


Last edited by ttx450cap on Jun Sat 20, 2020 10:25 pm, edited 1 time in total.
Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sat 20, 2020 10:17 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
hum.. 3 schematics, my unit is not all the same, maybe to soon to say.

I cannot make out if it's a blue or black dot on the 2rd and 3th dot. any ideas what the values is ?


Attachments:
cap_id1.jpg
cap_id1.jpg [ 641.95 KiB | Viewed 4183 times ]

_________________
only the dead fish go with the flow
Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 6:02 pm 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 5858
Location: Littleton, MA
That is the 50 pF mica capacitor off the grid of the 6SJ7.

The code reads 50 pF (grn-blk-blk), 600 volts (grn), 10% tolerance (gold)
http://www.tpub.com/neets/book2/3g.htm

Don’t mess with it unless it’s proven to be bad.

_________________
Steve Byan https://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 8:44 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
That is the 50 pF mica capacitor off the grid of the 6SJ7.

The code reads 50 pF (grn-blk-blk), 600 volts (grn), 10% tolerance (gold)
http://www.tpub.com/neets/book2/3g.htm

Don’t mess with it unless it’s proven to be bad.


colors dont seem that obvious to me.. :wink: thanks.. testing them if I can figure out what they are.

So far, many of the solar cap are in spec or close, but as for leakage no. I imagine running these at line voltage most of the service life, they dont like to change much.

_________________
only the dead fish go with the flow


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 8:46 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
here's one. You dont know unless..

surprise. glad I was updating to bnc plugs..


Attachments:
E-200.bnc.jpg
E-200.bnc.jpg [ 468.58 KiB | Viewed 4135 times ]

_________________
only the dead fish go with the flow
Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 9:18 pm 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 5858
Location: Littleton, MA
That’s part of the shielding for the RF outputs.

_________________
Steve Byan https://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 9:40 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
That’s part of the shielding for the RF outputs.


is not one of them a 4k resistor?

_________________
only the dead fish go with the flow


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 10:49 pm 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 5858
Location: Littleton, MA
ttx450cap wrote:
is not one of them a 4k resistor?

Yes, and it's buried in the shell of the connector to minimize the RF leakage to the low-level RF output.

_________________
Steve Byan https://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 10:58 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
here's an example of no listing in schematic. .1uf cap cannot find anywhere in any schematic and other items values are not what listed as values. I.e. I do not know if they just stated a 3k resistor value with 10% value and the tech put in what ever they could find or anything close to those values?

None of the 3 schematics and 4 listings, have listing of a .1uf cap

trying to match up the values best I can


Attachments:
.1uf.jpg
.1uf.jpg [ 602.07 KiB | Viewed 4123 times ]

_________________
only the dead fish go with the flow
Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Sun 21, 2020 10:59 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
ttx450cap wrote:
is not one of them a 4k resistor?

Yes, and it's buried in the shell of the connector to minimize the RF leakage to the low-level RF output.


If you did not know that.... thats why I pointed it out..

_________________
only the dead fish go with the flow


Top
 Profile  
 
 Post subject: Re: Precision Signal Generator E 200 and E 200 C
PostPosted: Jun Mon 22, 2020 7:04 pm 
Member
User avatar

Joined: May Sun 10, 2020 2:55 pm
Posts: 2254
Location: SW, MI
stevebyan wrote:
That is the 50 pF mica capacitor off the grid of the 6SJ7.

The code reads 50 pF (grn-blk-blk), 600 volts (grn), 10% tolerance (gold)
http://www.tpub.com/neets/book2/3g.htm

Don’t mess with it unless it’s proven to be bad.


all 3 failed at 25v leak test :( So all caps on the oscillator are bad.

there are 2 more and they are very hard to ID the colors besides the one you iD'ed 50pF

one thing I read said that first dot is normally white, upper left. Reading left to right, these have no White or Black dot for 1st. Which dot's are the characteristics and values? Is the bottom row Voltage, multiplier, tolerances?

Y, Gr, Blk -----> (not sure of the yellow very faint)
Red, Br, Gld

Or, Blu, Blu ----->
Gr, Br, Blu (not sure of the Brown, no paint)

_________________
only the dead fish go with the flow


Top
 Profile  
 
Post New Topic Post Reply  [ 213 posts ]  Go to page 1, 2, 3, 4, 5 ... 11  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: John Bartley and 24 guests



Search for:
Jump to:  




































Privacy Policy :: Powered by phpBB