6 Feb
2021
6 Feb
'21
1:25 p.m.
Hi all, I wonder if anybody has one with the terminators installed that
can read off the p/n for these SIPs
The manual says they are 8-pin 7 resistor 220/330 ones, but that is not
possible! To put 7 resistor pairs to 220 and 330 you need a 9-pin,
unless you have one resistor SIP for 220 and another for 330!? But there
are 2 so that leaves an odd number! The sockets are 9-pin.? I have yet
to find any 9-pin ones on digikey
cheers,
Nigel
--
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype: TILBURY2591 nw.johnson at ieee.org
6 Feb
6 Feb
2:44 p.m.
On 02/06/2021 03:25 PM, Nigel Johnson via cctalk wrote:
Hi all, I wonder if anybody has one with the
terminators installed that
can read off the p/n for these SIPs
The manual says they are 8-pin 7 resistor 220/330 ones, but that is not
possible! To put 7 resistor pairs to 220 and 330 you need a 9-pin,
unless you have one resistor SIP for 220 and another for 330! But there
are 2 so that leaves an odd number! The sockets are 9-pin. I have yet
to find any 9-pin ones on digikey
I have a differential 8200 here, it does not appear to have
any internal terminators, or anything pluggable on the SCSI
interface board.
Jon
2:48 p.m.
On Sat, Feb 6, 2021 at 1:26 PM Nigel Johnson via cctalk
<cctalk at classiccmp.org> wrote:
Hi all, I wonder if anybody has one with the terminators installed that
can read off the p/n for these SIPs
The manual says they are 8-pin 7 resistor 220/330 ones, but that is not
possible! To put 7 resistor pairs to 220 and 330 you need a 9-pin,
unless you have one resistor SIP for 220 and another for 330! But there
are 2 so that leaves an odd number! The sockets are 9-pin. I have yet
to find any 9-pin ones on digikey
I just took a look at one of my EXB-8200 tape drives. Unfortunately it
wasn't set up for internal termination and the resistor packs were
removed. It has (3x) 8-pin SIP sockets.
Bourns 4608X-104-221/331L / 4608X-104-221/331LF and 4308R-104-221/331L
parts are in stock at Mouser and Digi-Key. Those are 8-pin,
12-resistor dual termination networks.
(3x) 4608X-104-221/331 parts would have the necessary number for
terminations for single-ended SCSI:
https://www.bourns.com/pdfs/scsi.pdf
3:25 p.m.
I've got an 8200 here, but I'll have to open the enclosure to see. But
if it's a 7 pin device, the part number would be a Bourns
4607X-104-221/331L. Digikey claims to have them in stock.
--Chuck
3:28 p.m.
...and if a 9 pin SIP, the part number would be 4609X-104-221/331L.
They're a bit harder to find.
--Chuck
3:55 p.m.
I agree.? None on Digikey.? The manual says 7-resistor 8 pin, which is
impossible if one resistor on each pin goes to 5V and the other to Vss,
but the sockets are actually 9-pin!
If Chuck can give me a definite part number I will be on the way.? The
controller says it specifically supports an EXB 8200 so should be able
to make it work with a terminator!
cheers,
Nigel
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
?Amateur Radio, the origin of the open-source concept!
Skype: TILBURY2591 nw.johnson at ieee.org
On 2021-02-06 6:28 p.m., Chuck Guzis via cctalk wrote:
...and if a 9 pin SIP, the part number would be
4609X-104-221/331L.
They're a bit harder to find.
--Chuck
3:59 p.m.
I stand corrected, my 8200 has 3x 8-pin sip sockets!
Nigel
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype: TILBURY2591 nw.johnson at ieee.org
On 2021-02-06 5:48 p.m., Glen Slick via cctalk wrote:
On Sat, Feb 6, 2021 at 1:26 PM Nigel Johnson via
cctalk
<cctalk at classiccmp.org> wrote:
Hi all, I wonder if anybody has one with the
terminators installed that
can read off the p/n for these SIPs
The manual says they are 8-pin 7 resistor 220/330 ones, but that is not
possible! To put 7 resistor pairs to 220 and 330 you need a 9-pin,
unless you have one resistor SIP for 220 and another for 330! But there
are 2 so that leaves an odd number! The sockets are 9-pin. I have yet
to find any 9-pin ones on digikey
I just took a look at one of my EXB-8200 tape drives. Unfortunately it
wasn't set up for internal termination and the resistor packs were
removed. It has (3x) 8-pin SIP sockets.
Bourns 4608X-104-221/331L / 4608X-104-221/331LF and 4308R-104-221/331L
parts are in stock at Mouser and Digi-Key. Those are 8-pin,
12-resistor dual termination networks.
(3x) 4608X-104-221/331 parts would have the necessary number for
terminations for single-ended SCSI:
https://www.bourns.com/pdfs/scsi.pdf
4:23 p.m.
On Sat, Feb 6, 2021 at 3:59 PM Nigel Johnson via cctalk
<cctalk at classiccmp.org> wrote:
I stand corrected, my 8200 has 3x 8-pin sip sockets!
Nigel
OK, that matches my two EXB-8200 that I just looked at, and also these
images from eBay listings:
https://i.ebayimg.com/images/g/rh0AAOSwSdFe3p7v/s-l1600.jpg
https://i.ebayimg.com/images/g/Cq4AAOSwFNFf8B9i/s-l1600.jpg
https://i.ebayimg.com/images/g/Cr8AAOSwPbBf0Ajm/s-l1600.jpg
https://i.ebayimg.com/images/g/pkkAAOSwjylaob~P/s-l1600.jpg
https://i.ebayimg.com/images/g/C20AAOSwq4VaOqBm/s-l1600.jpg
The first image above shows (3x) 8-pin SIP parts installed, which
appear visually similar to the parts that are installed in the second
EXB-8200 I have. I don't recognize the part number. It appears to be
something like "WT04 9020", where "WT" could possibly be Walsin
Technology. I can find some datasheets for Walsin Technology WT04
surface mount resistor arrays, but not SIP parts. Maybe the "9020" is
a date code, and these are obsolete parts from that vendor and
datasheets are no longer available, or at least not easy to find.
In any case, current Bourns 4608X-104-221/331L / 4608X-104-221/331LF
or 4308R-104-221/331L parts might do the trick. (Or just cable it up
for external termination).
4:33 p.m.
Thanks for that. Pity the people who post on ebay don't give close-ups
of the resistor arrays!
My serial is 530573 so it should be a later rev that will work with the
cleaning cartridge.
I have some 4608X-104-221/331L currently in my digikey shopping basket -
I will place order on Monday after I confirm that the two outside pins
go to Vcc and Fss and the six others go to signal pins on the bus.
External not an option really - tight fit inside rack and more parts to
buy than three resistor packs!
Now off to browse ebay pictures :-)
Thanks again, Nigel
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype: TILBURY2591 nw.johnson at ieee.org
On 2021-02-06 7:23 p.m., Glen Slick via cctalk wrote:
On Sat, Feb 6, 2021 at 3:59 PM Nigel Johnson via
cctalk
<cctalk at classiccmp.org> wrote:
I stand corrected, my 8200 has 3x 8-pin sip
sockets!
Nigel
OK, that matches my two EXB-8200 that I just looked at, and also these
images from eBay listings:
https://i.ebayimg.com/images/g/rh0AAOSwSdFe3p7v/s-l1600.jpg
https://i.ebayimg.com/images/g/Cq4AAOSwFNFf8B9i/s-l1600.jpg
https://i.ebayimg.com/images/g/Cr8AAOSwPbBf0Ajm/s-l1600.jpg
https://i.ebayimg.com/images/g/pkkAAOSwjylaob~P/s-l1600.jpg
https://i.ebayimg.com/images/g/C20AAOSwq4VaOqBm/s-l1600.jpg
The first image above shows (3x) 8-pin SIP parts installed, which
appear visually similar to the parts that are installed in the second
EXB-8200 I have. I don't recognize the part number. It appears to be
something like "WT04 9020", where "WT" could possibly be Walsin
Technology. I can find some datasheets for Walsin Technology WT04
surface mount resistor arrays, but not SIP parts. Maybe the "9020" is
a date code, and these are obsolete parts from that vendor and
datasheets are no longer available, or at least not easy to find.
In any case, current Bourns 4608X-104-221/331L / 4608X-104-221/331LF
or 4308R-104-221/331L parts might do the trick. (Or just cable it up
for external termination).
5:51 p.m.
On Sat, Feb 6, 2021 at 4:33 PM Nigel Johnson via cctalk
<cctalk at classiccmp.org> wrote:
I have some 4608X-104-221/331L currently in my digikey shopping basket -
I will place order on Monday after I confirm that the two outside pins
go to Vcc and Fss and the six others go to signal pins on the bus.
I pulled the SIP packs out of my EXB-8200 because it is mounted in an
external case and the next time I go to use it I would probably attach
an external terminator to it without thinking that it was terminated
internally.
I measured ~91-Ohm between pin 1 and pin 8, which is the expected
value for (6x) (220-Ohm + 330-Ohm) in parallel.
I measured ~163-Ohm between pin 1 and each of pin 2, 3, 4, 5, 6, 7.
That is the expected value for 330-Ohm in parallel with (220-Ohm in
series with 110-Ohm ((5x) (220-Ohm + 330-Ohm) in parallel).
I measured ~145-Ohm between pin 8 and each of 2, 3, 4, 5, 6, 7. That
is the expected value for 220-Ohm in parallel with (330-Ohm in series
with 110-Ohm ((5x) (220-Ohm + 330-Ohm) in parallel).
So a 4608X-104-221/331L should be a functional equivalent (220-Ohm in
common to pin 8, 330-Ohm in common to pin 1).
6:08 p.m.
On 2021-02-06 8:51 p.m., Glen Slick via cctalk wrote:
On Sat, Feb 6, 2021 at 4:33 PM Nigel Johnson via
cctalk
<cctalk at classiccmp.org> wrote:
Thank you, Glen.? I will order some from Digikey on Monday.? So it seems
that the manual is lying when it says it has seven resistors - I didn't
think that was likely - in that case you would need a a separate pack
for the other side of the pull and there are 3 - not an even number.
I also powered up the unit and checked that I have 5V on on eend and
ground on the other, so all looks good.
Thanks to all for your help,
Nigel
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype: TILBURY2591 nw.johnson at ieee.org
I have some 4608X-104-221/331L currently in my
digikey shopping basket -
I will place order on Monday after I confirm that the two outside pins
go to Vcc and Fss and the six others go to signal pins on the bus.
I pulled the SIP packs out of my EXB-8200 because it is mounted in an
external case and the next time I go to use it I would probably attach
an external terminator to it without thinking that it was terminated
internally.
I measured ~91-Ohm between pin 1 and pin 8, which is the expected
value for (6x) (220-Ohm + 330-Ohm) in parallel.
I measured ~163-Ohm between pin 1 and each of pin 2, 3, 4, 5, 6, 7.
That is the expected value for 330-Ohm in parallel with (220-Ohm in
series with 110-Ohm ((5x) (220-Ohm + 330-Ohm) in parallel).
I measured ~145-Ohm between pin 8 and each of 2, 3, 4, 5, 6, 7. That
is the expected value for 220-Ohm in parallel with (330-Ohm in series
with 110-Ohm ((5x) (220-Ohm + 330-Ohm) in parallel).
So a 4608X-104-221/331L should be a functional equivalent (220-Ohm in
common to pin 8, 330-Ohm in common to pin 1).
10 Feb
10 Feb
3:07 p.m.
All suppositions correct - (or was it suppositories ?)
I got the SIP resistor packs today from Digikey.? I ordered
4608X-4-221/331L but what came was marked just 8x-4-221-331L
Works fine, now Diloq SQ703 recognises the drive and built-in diags
print a response. NetBSD recogised it as a TK50.
Now I am waiting for a shipment of cassettes to try it out!
Thanks to all who had useful suggestions.
Nigel
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype: TILBURY2591 nw.johnson at ieee.org
On 2021-02-06 8:51 p.m., Glen Slick via cctalk wrote:
On Sat, Feb 6, 2021 at 4:33 PM Nigel Johnson via
cctalk
<cctalk at classiccmp.org> wrote:
I have some 4608X-104-221/331L currently in my
digikey shopping basket -
I will place order on Monday after I confirm that the two outside pins
go to Vcc and Fss and the six others go to signal pins on the bus.
I pulled the SIP packs out of my EXB-8200 because it is mounted in an
external case and the next time I go to use it I would probably attach
an external terminator to it without thinking that it was terminated
internally.
I measured ~91-Ohm between pin 1 and pin 8, which is the expected
value for (6x) (220-Ohm + 330-Ohm) in parallel.
I measured ~163-Ohm between pin 1 and each of pin 2, 3, 4, 5, 6, 7.
That is the expected value for 330-Ohm in parallel with (220-Ohm in
series with 110-Ohm ((5x) (220-Ohm + 330-Ohm) in parallel).
I measured ~145-Ohm between pin 8 and each of 2, 3, 4, 5, 6, 7. That
is the expected value for 220-Ohm in parallel with (330-Ohm in series
with 110-Ohm ((5x) (220-Ohm + 330-Ohm) in parallel).
So a 4608X-104-221/331L should be a functional equivalent (220-Ohm in
common to pin 8, 330-Ohm in common to pin 1).
1178
days inactive
1182
days old
11 comments
4 participants
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cclist＠sydex.com -
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