EICO 369 Sweep / Marker Generator
 

I picked this EICO 369 sweep/marker generator recently. I was really happy to get the specialized cables with it. This device use post marker injection which is a better approach I think. That works by connecting the DEMOD probe to the output of the DUT, a marker is mixed in and the output goes to a scope.
http://farm5.static.flickr.com/4041/...6f4bd844_b.jpg

http://farm5.static.flickr.com/4019/...4a3c082a_b.jpg

http://www.bobandersen.com/images/EICO%20369/01-03.jpg

The sweep is achieved by passing 60 Hz AC through this iron core thingy.
http://www.bobandersen.com/images/EICO%20369/01-04.jpg

I replace one tube that had gone to air and did a recap.
http://www.bobandersen.com/images/EICO%20369/01-01.jpg

It's working OK, but the output is distorted on the lower bands. I wonder if this is normal :scratch2:
http://www.bobandersen.com/images/EICO%20369/02-03.jpg http://www.bobandersen.com/images/EICO%20369/02-02.jpg http://www.bobandersen.com/images/EICO%20369/02-04.jpg

I'm curious to see how it measures up to my Hickok 615.

I bought one of these last night along with an older RCA Oscilloscope. I may have to recap and troubleshoot them. We will see. I hope my tubes get here soon for the TA129, I'm going to go broke hanging out on ebay! Actually I have less than $50 into both of them and so far and I have been pleasantly surprised in that everything I've bought works well and was better than expected. Knock on wood! Do you have a manual for the 369? If the one I bought doesn't I may ask if you can scan it. If not I will find one. I will try BAMA now.

Found it! I love that site. 2 minutes later and the manual is on my computer and I'm posting a "never mind".

LOL - eBay can be a dangerous place.
I do have the original manual with somewhat different addendums at the back. They made a number of minor improvements to the design over time.

Did you get the probes with yours ? If not, you'll need to fabricate some with the proper termination.

It was fairly easy to recap since there's only one can to deal with. I hope you get yours running so we can compare outputs :)

I was much more worried about the oscilloscope. Its a RCA WO 535A. He had a "BIN" on it for $120 so I assume its pretty decent. If not I only paid $11. Originally I was looking at later model Tektronics models and could of had some in the $50 to $75 range that I'm sure would work great and come with documentation. I decided to throw the die again. I have no idea what I am getting but for $11:scratch2: It will take a little while to get it figured out if it doesn't come with probes and documentation. I've watched every video there is on youtube about oscilloscopes to see if I could figure it out just from a picture of the front of it and I think I can.

Forgot to answer the question about the signal generator. I don't know:scratch2: I think so. Ya gotta love ebay! For $9 again, I get what I get:yes: I've just been too lucky lately or as I've tried to post elsewhere Ebay is dying a slow death and I'm taking advantage of it or both. The economy has picked up a little but I can't sell things for half what I was getting a year ago so I have just about closed up shop. High quality high demand things will continue to sell wherever they are sold. An Oscilloscope and a signal generator do not have a high demand:D.

Ok, an update to the above. The RCA Scope came last night with probes and working. The pots in the unit are a little shaky but nothing a little deoxit won't take care of. Very happy considering the cost. The Eico 369 was not as great a deal but I'm not complaining. It did not have any cables with it. I have a feeling I'm probably gonna have to rig something up. The unit itself is clean with only 1 bad tube. I am going to chance it with my existing capacitors until I see the signal. It looks as though it was built in 1968? I have plenty of items that old with original capacitors. Another 10 or 15 years older and it would be a no brainer the opposite direction. Have an opinion? Since Bob recapped his:o Also any ideas on cables would be appreciated.

I'm glad your scope is working :)

Once I replace the dead 6RD7, mine worked with the original caps. I recapped it mostly in the hope the output sine wave purity would improve, but it didn't.

I recently came across this thread which discusses modifications to improve performance. I also have some addendums with recommended modifications. I've ordered up some parts and will give them a try soon.

You will need to make up some cables. There are some passive components inside the pods at the ends of the original cables you should replicate. I think they show them in the documentation.