Eico 666/667 Repair Parts 12 Mar 2024 "Mike" mike@fourwater.com I have a limited quantity of repair parts available. Prices shown are for one item each. Shipping and handling is extra. The postage cost depends on the address the parts will be sent to. Calibration and Leak Test Section: Capacitor 10uF 250V, $4.00, For calibration and leak test power supply Diode 1N4004, $1.00, (selenium replacement) For calibration and leak test power supply Resistor 270K Ohms, $0.50, (metal film replacement) For calibration and leak test section (two are used) Potentiometer 100K Ohms, $10.00, (sealed) For calibration and leak test section (two are used) Grid and Plate Potentiometers: Potentiometer 5K Ohms 5W 20% w/spst switch, $20.00, Grid control replacement (see notes below) Potentiometer 3.3K Ohms 5W 5%, $15.00, Plate control replacement (includes separate 27K resistor - see notes below) Transitor Test Section Parts: Capacitor 10uF 50V, $1.00, For transistor test section power supply Diode 1N151, $2.00, (1N34 replacement) For transistor test section power supply Resistor 680 Ohms, $0.50, (metal film replacement) For transistor test section power supply Resistor 1000 Ohms, $0.50, (metal film replacement) For transistor test section Protection Parts: Diode 1N4148, $2.00, For meter protection (two diodes provided) Lamp #49, $2.00, For Grid pot protection Lamp Socket, $2.00, For grid pot protection Other Parts: Lamp #47, $2.00, For power indicator lamp replacement Notes: My prices are higher because I have to buy them just like everyone else and pay for postage. If you prefer, you can get the parts directly from regular suppliers such as Digikey, Mouser, Newark or another supplier. Don't worry, I won't get mad if you do. I'm just providing these parts as a service. Before you try to replace the grid or plate control, see if it is repairable. Depending on your situation, the existing controls may be repairable, or the problem may not even be the control (it could be the switches). See the files http://www.fourwater.com/files/restr666.txt and http://www.fourwater.com/files/eico666-667-repair.txt for more information. Grid control: Note: I only have one replacement grid control left, but you can buy it direct yourself from a supplier such as Digikey, Mouser, Newark or another supplier. This should be a 5% potentiometer, however the 20% is the best I can currently find. It is possible to custom order the correct 5% potentiometer, but it requires a very large quantity which is not economically feasable. The 20% does work in the testers, but there is a potentially slight error due to the tolerance difference. However, the error is going to be much less than 20%. It is the linearity of this potentiometer that is important, not the overall tolerance. The exact error though is dependant upon test configuration (see the eico666-667-repair.txt file for details). Still, having a working tester with slightly more error in the results is better than no tester at all. Plate control: Currently I have eight of these controls available. Currently there are no 3K wirewound 4W 5% potentiometers available (except through a very large quantity custom order). However, I did find a few 3.3K 5W 5% potentiometers that can be installed instead. That puts the error at 15% worse case. However if you install a 27K resistor between the two wires that connect to the plate control, that can reduce the error to less than 9%. (The resistor is included with the potentiometer purchase). That puts the part within the stated tolerance for the pot in the Eico parts list (10%). In addition, these parts use metric shaft mounts. That means they are slightly larger that the orginal Imperial mount shafts. Depending on the hole in the tester, you may have to use a file to slightly enlarge the hole to get it to fit. Also, don't lose the mount nut. Since it is metric, the old control nut won't work. As noted above with the grid control, having a working tester is better than none at all because of a bad control. Calibration trimmers: I have four (sets of two) of the 100K trimmers available, plus two sets of 150K trimmers. The calibration trimmers can be 100K to 150K trimmer pots. They should be sealed pots so they don't go bad on you again. The original trimmers are 100K, but 150K are perfectly acceptable replacements. A trimmer larger than 150K could be used, but it will make adjusting the calibration difficult as the adjustment resolution will be overly narrow. Don't use anything less than 100K. You need at least a +-50K adjustment range. The trimmers should be linear taper. You could possibly use audio taper, but as with using too large of a resistace, it will make adjustment difficult. How To Order: Reference: http://www.fourwater.com/equip/eico666-667-parts.txt To order, contact "Mike" mike@fourwater.com Send me an email indicating the item(s) you want. Please include your shipping address. I will let you know the total price including shipping and handling. Note: I can only accept a check or money order (US dollars only). Sorry, International orders are not accepted. Items are shipped via USPS.