Is there an Error in the/this 48k Issue 2 Schematics?

[1bvl109]

There is this thread about fixing the issue 3B to 4B schematics viewtopic.php?f=22&t=1528&p=21755&hilit ... ics#p21755

However there also seems to be an error in the issue 2 schematics linked there http://www.retroisle.com/sinclair/zxspe ... matics.gif also e,g. here https://spectrumforeveryone.com/wp-cont ... matics.gif on the middle left side near the EAR line.

Shouldn't EAR be connected through R37 1k to V0, i.e. ground?



I'm a little confused here, because all issue 2 schematics I could dig up seem to contain this error - if it actually is an error.

And by the way. what do all this BK, FT, RT, LT and whatnot peppered throughout the schematics signify?

[1024MAK]

However there also seems to be an error in the issue 2 schematics linked there http://www.retroisle.com/sinclair/zxspe ... matics.gif also e,g. here https://spectrumforeveryone.com/wp-cont ... matics.gif on the middle left side near the EAR line.

Shouldn't EAR be connected through R37 1k to V0, i.e. ground?



I'm a little confused here, because all issue 2 schematics I could dig up seem to contain this error - if it actually is an error.

Yes, that is an error, R37 should have one end connected to 0V/GND. There are many errors on the issue 2 schematics.
All these schematics originate from the same drawings, hence all have the same errors (unless at some later stage, someone has noticed and corrected an error).

And by the way. what do all this BK, FT, RT, LT and whatnot peppered throughout the schematics signify?

Relates to the position of the component leads on the board, BK - back, FT - front, RT - right, LT - left...

Mark

[1bvl109]

Yes, that is an error, R37 should have one end connected to 0V/GND.

Relates to the position of the component leads on the board, BK - back, FT - front, RT - right, LT - left...

Thank you captain. Heading for the alpha quadrant. Course set.