Please click your language flag. Bitte Sprachflagge klicken.

CANDOHM resistor zenith: (5-S-218AT Ch=5521AT); 5S218AT

Martin Renz Ernst Erb Vincent de Franco Martin Bösch Mark Hippenstiel Bernhard Nagel Dietmar Rudolph † 6.1.22 Otmar Jung Heribert Jung Eilert Menke 
Please click the blue info button to read more about this page.
Forum » Radios and other type of sets (Physics) etc. » MODELS DISPLAYED » CANDOHM resistor zenith: (5-S-218AT Ch=5521AT); 5S218AT
Meyer Rochwerger
Meyer Rochwerger
BR  Articles: 115
Schem.: 320
Pict.: 1802
23.Aug.09 13:49

Count of Thanks: 6
Reply  |  You aren't logged in. (Guest)   1

This model radio employs a three section "candohm" resistor (R10) working as a voltage divider to obtain the negative bias voltages for the 6Q7G and 6F6G tube grids.

The schematics does not gives the ohm values for this "candohm".

I've search over to get these.. but has no success.

I wonder if maybe someone could give a clue with this matter.

attached is a schematics with all the voltages.





This article was edited 25.Aug.09 11:16 by Meyer Rochwerger .

Todd Stackhouse
USA  Articles: 151
Schem.: 44
Pict.: 30
29.Aug.09 06:37

Count of Thanks: 7
Reply  |  You aren't logged in. (Guest)   2

On a schematic of a 6-S-52 Zenith I found a six-section Candohm.  Three of the six sections performed the same functions as the three-section Candohm in your 5-S-218AT.  Those values are actually given  on that schematic and the three sections in question would be:

first section, from center tap of HV winding/- side of 8µF 450V to 220k/1M/g1 of 6Q7: 250 ohms

second section, from 220k to k/g3 of 6F6G: 74 ohms

third section, k/g3 of 6F6G to earth/ground: 83 ohms.

I don't know if you have tried measuring any of the actual resistances of your original Candohm to see if any of these values match or are at least close, but these could be a starting point...these would probably need to be multi-watt resistors; and these exact values are not readily available; you would need to substitute probably 240 or 270 ohms for the 250, 75 ohms for the 74, and 82 ohms for the 83,,,

Wünsch' dir viel Glück!