Input Voltage selector missing on a TRIO 15Mhz CS-1560A ][ scope - Page 1
Forum section: electronics / projects

author: FearTec
author_rank: Regular Contributor
timestamp: May 31, 2014, 02:46:56 pm
content: HelloI am trying to power up a TRIO 15Mhz CS-1560A ][. I am a newbie +1 and was handed the scope as a repair job to play with and learn from.I have heaps of pics below of this beautiful 1971 scope.I think the problem is a missing power selector switch that has fallen off the back (I changed the fuse assuming that was it).I checked the diagram from the original manual and it does require a connection for voltage input selection. I opened it up to confirm.I followed the wires to the taps on the transformer and to other areas of the unit (marker is removable with pure alcohol).This is the rear of the power input selection panelI have the correct 500mA fuse that the manual says to install with 240v (even though the diagram says 1A.Q1) Should I source a power selector plug or can/should I connect the right points with appropriate gauge wire to connect the loop safely?I have no idea what to connect to replicate the 240 input selector.Diagram:http://simon.fearby.com/temp/eev/scope/diagram.JPGI spotted fgsantos7 theadhttps://www.eevblog.com/forum/projects/kenwood-trio-cs-1560a-help/msg243058/#msg243058and a link to the service manualhttps://www.dropbox.com/s/1or63g1uq3ztws0/Trio%20CS-1560A%20Oscilloscope%20Service%20Manual.pdf.Any advice appreciated. Thanks In AdvancePron PicsCopper Heatsink:Multi-leg Crystal?Nice Curved Traces:

author: SeanB
author_rank: Super Contributor
timestamp: May 31, 2014, 03:08:02 pm
content: Jumpers will work, as you only need 3 for 240V selection. the multi legged can is an IC in TO100 packaging, easy to see by the silkscreen under saying IC103.I got a Kenwood from Frankie with the same voltage selector, I can probably photograph it and measure the pin connections of it if you want.

author: FearTec
author_rank: Regular Contributor
timestamp: May 31, 2014, 03:12:48 pm
content: >Jumpers will work, as you only need 3 for 240V selection.Awesome, I need as much guidance as possible to connect the voltage (mains) to boot his puppy.Any probing of yours would be appreciated (or photos of the missing plug).Thanks In Advance

author: SeanB
author_rank: Super Contributor
timestamp: May 31, 2014, 03:20:21 pm
content: Here are a few quick pics.....

author: SeanB
author_rank: Super Contributor
timestamp: May 31, 2014, 03:28:15 pm
content: Seems to match. Looking at the connector in SAM102 there are 2 rows of pins, top and bottom. We will designate the top row as that one with the arrow head. Looking from back, top row has 3 pins evenly spaced. Left pin from back shows no continuity to any other pin, likely there for stability. Middle pin only has continuity to the pin below it, nowhere else. Pin on right has continuity to the pin below and the middle pin at the bottom. Thus the bottom row with 3 pins on the right has the leftmost one to he middle of the top, and the other 2 connected to the top rightmost pin.Hope this helps, i am going out now, so good luck with it.My thanks to Frankie and Martin Lorton for the scope this demo came from.

author: Unknown
author_rank: Unknown
timestamp: May 31, 2014, 04:01:38 pm
content: I've got the 1577A, and it appears my jumper module connections are exactly the same as what Sean describes.

author: SeanB
author_rank: Super Contributor
timestamp: May 31, 2014, 07:45:08 pm
content: I think these were common on Japanese made scopes, as they were likely to have it changed often.Jucole, does yours have the plastic cover that blanks the unused socket positions still? It just is a plastic strip with 10 holes punched into it, and a little longer than the selector so that it covers the socket fully whatever position the switch is placed.

author: Unknown
author_rank: Unknown
timestamp: June 01, 2014, 10:25:52 am
content: Quote from: SeanB on May 31, 2014, 07:45:08 pmsadly no; it was a unit only from Ebay some 5 years when I started electronics.

author: SeanB
author_rank: Super Contributor
timestamp: June 01, 2014, 11:42:22 am
content: Same as me then.

author: FearTec
author_rank: Regular Contributor
timestamp: June 01, 2014, 08:19:18 pm
content: Thanks so much for your help everyone, I'll replicate the connections and give it a go