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It's scope week
#1

at Radioroslyn. Since Mike got my dad's old Tek 465 up and running I thought I'd have a go at my old Heathkit HO-10.
It's designed to be used a as signal monitor scope in a ham station vintage about 1963. Haven't used it in 15yrs or so. Flipped it on a while back and it had no trace. This preciptated a rebuild of the power supply. Now if I had longer arms to reach into my deep pocket I could order a capacitor kit from Hayseed Hamfest @ $60. But I don't so I rebuilt a can to fit it. Back in the 60's you could easily get HV electrolytic cap in a wide variety of voltages. Now days it's pretty much 160,250,and 450v.
Had to use a slightly taller can as all of the replacement were 450v (3-22mf and 1-33mf) and a couple of 40mf @ 350v wired in on the chassis. Along with these there is also a pair of .15mf@ 1.5kv (HV filters for the crt anode voltage). Used 3 .68@ 630v to get about .2@1890v. A common issue with these scopes is that the .15mf cap will short and take the 1550v winding on the power transformer. That pretty much renders it scrap.
Got all of that replaced and found a few problems, couple of resistor way out and a broken wire of two. After that power it up and it was back to normal. Tweaked the CRT a bit so the trace was straight.
Manual is here  http://www.rsp-italy.it/Electronics/Kits...0scope.pdf
It's really a bare bone scope but does have some handy features like a tone generator that you can hook into your transmitter audio to check for distortion and level of modulation. Can be used to monitor radio signal though a receivers IF stage. Want to give that a try with the old HRO set.
Pictures @11pm.


Attached Files Image(s)
   

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


Messages In This Thread
It's scope week - by Radioroslyn - 05-18-2017, 07:32 PM
RE: It's scope week - by Radioroslyn - 05-18-2017, 10:34 PM
RE: It's scope week - by morzh - 05-18-2017, 10:41 PM
RE: It's scope week - by Radioroslyn - 05-18-2017, 10:51 PM
RE: It's scope week - by WallaceRoger - 05-19-2017, 02:06 PM
RE: It's scope week - by morzh - 05-19-2017, 02:35 PM
RE: It's scope week - by Eliot Ness - 05-19-2017, 04:12 PM
RE: It's scope week - by morzh - 05-19-2017, 04:27 PM
RE: It's scope week - by Radioroslyn - 05-19-2017, 07:47 PM
RE: It's scope week - by WallaceRoger - 05-20-2017, 02:03 PM



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