Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

Help with Eico 950B knob and pointer
#5

Roger,

Yes, it is Charles.

I use Chas in many forums, seems it was available...

I have capacitance meters, most are old school bridge type.

You will find that long leads will become part of the measurement. In open space, 8" clips leads will give 10pf, twist the leads together and it will go quite a bit higher. So it is best to measure right at the binding posts.

Caps that are leaking a LOT will have a very broad and slight wink to the eye. The overall quality of the cap is indicated by how sharp/deep the null. Really, should not be used to evaluate quality, just the ball park value and leakage under high voltage.

I keep a couple of 1% cap values as standards on the bench, in event I get a out of whack reading...

I found that as I service, I don't bother with common paper caps, just replace. Others that seem questionable and may be a more modern cap I will measure.

Truth be said I seldom use the bridge. It gets pressed into service when the radio won't align, generally, mica fixed padders are off or coil forms have shrunk. So I have to measure to know how far to pad out a cap to achieve alignment.

Oh, I do not know the full functions of the Eico, but if places over 600 volts on the cap, be careful. A large cap can recover some of the charge even after discharge in the bridge. Painful. Fair warning, it is not good for an ordinary cap over 1 mf to be discharged by shorting. The high current flow can breakup metalizing on those types or the internal connections on those with foils. Caps used in camera flashes can take it but still should have a resistor to discharge.

Useful tool...

Chas

Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”


Messages In This Thread
RE: Help with Eico 950B knob and pointer - by Chas - 05-03-2019, 07:35 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
under chassis parts locator diagram for 1938 Zenith 9s262
Has anyone gone to the trouble of creating an under chassis parts locator image?  Yes, I can identify components by foll...bobloney — 08:57 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Try looking at this site the book mark is for a old generator that I was given. David    https://radionerds.com/index.ph...David — 08:36 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Hello Everyone, I am looking for voltage identification for all the pin positions on the socket of a CRV-20130 power su...Tonym4704 — 08:16 PM
Philco P45-6365 Universal Transformer Instruction Manual
Can anyone guide me to where this may be found?GRG — 03:00 PM
54C Complete Teardown/Rebuild
I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM
HiFi (Chifi) tube amp build - but my own design.
It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM
Philco 71 Code 125
Hello,  I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM
Stromberg Carlson 1500 Squeal
And life just keeps getting more complicated.dconant — 07:57 AM
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM

[-]
Who's Online
There are currently no members online.

>