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Old 3rd Sep 2019, 7:07 pm   #21
ms660
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Join Date: Apr 2011
Location: Cornwall, UK.
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Default Re: Kolster-Brandes MR10

Quote:
Originally Posted by DonaldStott View Post
Before going any further I need to answer one key question - the K-B MR10 has a waveband/gram switch and page 3 of the Service Sheet 1233 has details of the Switch Table and Diagrams.

I can't really make much sense of this or properly view the waveband switch units from the end of the inverted chassis??
It's quite straightforward once you know the system that the Trader sheets use.

Almost all Trader sheet representations of the switches in the circuit and the actual switch contact layout diagrams use the same system, this makes it easy to understand for any manufactures model because they are all drawn using the same system.

1) All the switches are numbered on the schematic with a circuit reference, ie: S1, S2, S3 etc.

2) They are also shown in the switch table, the switch table shows which of the switch contacts are closed and which are open for the particular function that's been selected, a dash indicates open and a c indicates closed, for example when the control is set to gram in your receiver switch contacts S5 and S14 are closed, all the rest remain open.

3) Below the switch table are shown the switch contacts diagrams, each one has a number within a diamond for identification purposes in the chassis layout drawing, in this case there are only two switch wafers so they are numbered 1 and 2 respectively, if you look at the chassis layout pertaining to the inverted chassis you will see the two diamonds with the numbers in them close to the switch wafers, there's also an arrow attached to each one to show the direction viewed.

So far so good.

4) Next it's back to the switch diagrams again, each tag that is part of the switching in the schematic has a number corresponding to the switch number in the schematic, ie: S2, S3, S4 etc, you will notice that in the diagram that the curve that they relate to also has another contact that isn't labeled, that contact is the wiper for those contacts on that curve, in other words it's common to those switches as depicted in the schematic.

As an example for switch S8 look at switch drawing number 2, switch 8's contacts as shown in the schematic are the one at 12 o'clock and the one at 10 minutes before 12 o'clock.

Lawrence.

Last edited by ms660; 3rd Sep 2019 at 7:13 pm.
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