Oh my gosh, it looks like this is almost exactly what I did. I'm not sure if I did it on my own accord, or if I was following the work of the previous person to work on the scope, but my new electrolytics are going to the wrong side of the 500 Ohm resistor. I will have to see if this fixes my noise problem!
Indeed, this made a huge improvement! Now I can actually troubleshoot the remaining issues and do an alignment. You have likely saved my scope from some unnecessary mutilation, and saved me time I didn't have to spare for troubleshooting. Thank you for posting this! I wonder if it used to be standard practice to float the ground of the filter capacitors... I would be interested to hear from anybody who knows why this decision was made in the design.
I'm happy to learn that it helped someone. Thank you for replying. I don't know the design answer, but I'm working on my third scope restoration right now and EICO is the only one I've found in that limited pool to do this. The other two were a vintage Dumont 164 and a vintage Hickok 640, where the Hickok is giving me fits.
Thanks for sharing your experience with the Eico 460. I’m starting a refurb on a 460 that looks ‘less than mint.’ Would you be willing to share a pdf of the assembly instructions? Even before watching your video I made the decision to replace all the caps (minus the mica caps) I’m impressed with your results! I hope I can achieve a similar outcome. W7GTM
I’m sorry I didn’t get back to you on this. I must have missed it. Let me know if you still want or need this and I’ll dig out the manual and photograph it.
Oh my gosh, it looks like this is almost exactly what I did. I'm not sure if I did it on my own accord, or if I was following the work of the previous person to work on the scope, but my new electrolytics are going to the wrong side of the 500 Ohm resistor. I will have to see if this fixes my noise problem!
Indeed, this made a huge improvement! Now I can actually troubleshoot the remaining issues and do an alignment. You have likely saved my scope from some unnecessary mutilation, and saved me time I didn't have to spare for troubleshooting. Thank you for posting this!
I wonder if it used to be standard practice to float the ground of the filter capacitors... I would be interested to hear from anybody who knows why this decision was made in the design.
I'm happy to learn that it helped someone. Thank you for replying. I don't know the design answer, but I'm working on my third scope restoration right now and EICO is the only one I've found in that limited pool to do this. The other two were a vintage Dumont 164 and a vintage Hickok 640, where the Hickok is giving me fits.
Thanks for the info. I feel like there might be some lesson about ground loops that I should find in all this... @@pinballpsycho
Thanks for sharing your experience with the Eico 460. I’m starting a refurb on a 460 that looks ‘less than mint.’ Would you be willing to share a pdf of the assembly instructions?
Even before watching your video I made the decision to replace all the caps (minus the mica caps)
I’m impressed with your results! I hope I can achieve a similar outcome.
W7GTM
I’m sorry I didn’t get back to you on this. I must have missed it. Let me know if you still want or need this and I’ll dig out the manual and photograph it.