The N8VEM Home Brew Computer Project

 

ECB Bus Monitor Parts List

Page history last edited by Andrew Lynch 1 mo ago
N8VEM ECB PARTS LIST    
**********  PRELIMINARY - 10/13/08 ***********
**********  10/14/08 - C6 changed to 33 pF
       
U1 74LS273    
U2 74LS273    
U3 74LS273    
U4 74LS273    
U5 74LS05    
U6 74LS30    
U7 74LS85    
U8 74LS85    
U9 74LS85    
U10 74LS85    
U11 74LS07    
U13 74LS00    
U14 74LS123    
U15 74LS123    
U16 74LS123    
U21 74LS241    
U22 74LS241    
U23 74LS241    
U24 74LS241    
U25 74LS241    
       
C1 220-560 pF  
C2,3,4,5,7,8  22 uF    
C6 33 pF    
C11-30 0.1 uF    
       
D1 AA119 (germanium)  
       
RR1,2,3,4,8 270 x 8 SIP  
RR5 4700 x 8 SIP  
RR6,7 1000 x 8 SIP  
RR9 2200 x 8 SIP  
       
R1,3 10K    
R2 330    
R4,5,6,7,9 27K    
R8  4700    
R10-16 270    
       
SW1,2,1_2,3_4 8 pos DIP    
BAR1-5 10 pos LED bar  

 

 

 

From Rich Cini: "The ECB pushbutton is E-SWITCH 700SP7B20M6QE (Digi-Key EG2596-ND) -- it¹s a little expensive ($4.50 or so)."

 

IMPORTANT CONSTRUCTION NOTE:

 

Hi All,

 

 

I just discovered I made an error in the ECB bus monitor PCB layout.  U13, U11, and U5 are missing connections to VCC and GND pins and you will have to add jumper wires manually.  I apologize for the error and want you to know about it and the remedy as quickly as possible.

 

 

If you are assembling your ECB bus monitor, please add the appropriate jumper wires from the bypass capacitor in front of the effected ICs.  With the PCB on its side and DIN 41612 to the right, the top pin of the bypass capacitor is VCC and connects to Pin 14 of the IC.  The bottom pin of the bypass capacitor is GND and connects to pin 7 of the IC.

 

 

The problem came about as the KiCAD part library did not fully/properly support the 74LS00, 74LS05, and 74LS07 ICs.  I made a substitution from another library which had slightly different layout rules and apparently missed that the ICs VCC and GND pins were not connected.

 

 

The required modifications should not affect functionality and if done on the copper side of the PCB with short jumpers should only minimally detract from the appearance of the final board.  I will update the design information as appropriate.

 

 

Again, I apologize for the inconvenience.

 

 

Thanks and have a nice day!

Andrew Lynch

 

 

Here is some explanation for the ECB bus monitor videos

 

http://www.hd64180-ecb.de/html/video.html

 

 

Comments (1)

profile picture

Andrew Lynch said

at 11:40 am on Dec 13, 2008

What are the builders using for T1? It is a PCB mounted momentary contact switch. I recall Rolf posting something about it on the forum a while back...

Thanks and have a nice day!

Andrew Lynch

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