ECI power supply help - UK Vintage Radio Repair and Restoration Discussion Forum

Brownmule · 26th Sep 2019, 10:37 pm

Hello ive got an older eci power supply im looking for a manual and maybe schematic. Ive contacted eci and was told they didn't keep records that old, any help would be greatly appreciated.

feldmakg · 4th Oct 2019, 2:35 am

Hi,
I just purchased the same unit minus the case at an Antique Radio Conference in Rochester, New York. I cleaned up the Power Supply and made a metal case for it. I lucked out and my unit was in working order when purchased.

I was using the PS to calibrate an old Simpson 260 VOM. Unfortunately, I accidentally shorted out the 300 volt power. White smoke. I metered all the transistors and Diodes. I blew out the Delco DTS-801 NPN output transistor on the back heat sink, a resistor and the fuse. The resistor and fuse were easy to replace. I metered the other transistors and Diodes and they look okay.

Component values and part numbers are labeled on the circuit board. Many of the transistors in the unit are no longer made. Specs are available on Google. New Old Stock Replacements can be found on Ebay. There are two integrated circuits in the power supply. A uA723 voltage regulator and a 555 timer chip. Both are readily available.

I found a source for the exact Output Transistor in England. However, cost was $20 plus shipping plus a long ship time. I ordered a 2SC3059 transistor locally for $3.00 plus shipping. A spec comparison suggests it will work. I have my fingers crossed.

There are two integrated circuits in the power supply. A uA723 voltage regulator and a 555 timer chip. Both are readily available. Ditto for the diodes.

I've also looked on the internet for a schematic without any luck. Its a pain to reconstruct the schematic from the circuit board. Again, the labels on the circuit board help. For instance, the transformer lead voltages are labeled.

Anyway, good luck and please post a source for the schematic if you find one.

Ken
KB3MDT

feldmakg · 5th Oct 2019, 4:00 am

Hi, I found the manual for the HV Power Supply (0-300 VDC, 0-50V DC bias, 12 VAC). It's at:-

www.ebaman.com

on the web. I believe you have to register to be able to download. Anyway, the file name is ECI_20600-20620_Hi_Voltage_Pwr_Sup. (Just search on ECI_20600 after LOGGIN IN and you will find it). Worst case, its in the repository in the Electronics/Test-Equipment/Various-Equipment folder. Good luck.

Ken
KB3MDT

26th Sep 2019, 10:37 pm	#1
Brownmule Retired Dormant Member Join Date: Sep 2019 Location: Madisonville, Tennessee, USA. Posts: 1	ECI power supply help Hello ive got an older eci power supply im looking for a manual and maybe schematic. Ive contacted eci and was told they didn't keep records that old, any help would be greatly appreciated. Attached Thumbnails

4th Oct 2019, 2:35 am	#2
feldmakg Retired Dormant Member Join Date: Oct 2019 Location: Macungie, Pennsylvania, USA. Posts: 2	Re: ECI power supply help Hi, I just purchased the same unit minus the case at an Antique Radio Conference in Rochester, New York. I cleaned up the Power Supply and made a metal case for it. I lucked out and my unit was in working order when purchased. I was using the PS to calibrate an old Simpson 260 VOM. Unfortunately, I accidentally shorted out the 300 volt power. White smoke. I metered all the transistors and Diodes. I blew out the Delco DTS-801 NPN output transistor on the back heat sink, a resistor and the fuse. The resistor and fuse were easy to replace. I metered the other transistors and Diodes and they look okay. Component values and part numbers are labeled on the circuit board. Many of the transistors in the unit are no longer made. Specs are available on Google. New Old Stock Replacements can be found on Ebay. There are two integrated circuits in the power supply. A uA723 voltage regulator and a 555 timer chip. Both are readily available. I found a source for the exact Output Transistor in England. However, cost was $20 plus shipping plus a long ship time. I ordered a 2SC3059 transistor locally for $3.00 plus shipping. A spec comparison suggests it will work. I have my fingers crossed. There are two integrated circuits in the power supply. A uA723 voltage regulator and a 555 timer chip. Both are readily available. Ditto for the diodes. I've also looked on the internet for a schematic without any luck. Its a pain to reconstruct the schematic from the circuit board. Again, the labels on the circuit board help. For instance, the transformer lead voltages are labeled. Anyway, good luck and please post a source for the schematic if you find one. Ken KB3MDT

5th Oct 2019, 4:00 am	#3
feldmakg Retired Dormant Member Join Date: Oct 2019 Location: Macungie, Pennsylvania, USA. Posts: 2	Re: ECI power supply help Hi, I found the manual for the HV Power Supply (0-300 VDC, 0-50V DC bias, 12 VAC). It's at:- www.ebaman.com on the web. I believe you have to register to be able to download. Anyway, the file name is ECI_20600-20620_Hi_Voltage_Pwr_Sup. (Just search on ECI_20600 after LOGGIN IN and you will find it). Worst case, its in the repository in the Electronics/Test-Equipment/Various-Equipment folder. Good luck. Ken KB3MDT