On 03/09/2015 20:31, Stephen Lafferty wrote:
--- Thought I had a longer list somewhere but this
short list is what I
find at the moment:
I think you'll find a 380 and a 384 are not the same :-) But the 8270/8271
substitutions by 74178/74179 seem to match and are good to know.
A leading additional 5 or 9 means DEC selected examples of devices, eg
97401/7401, 380/5380, etc against some particular criteria, such as
leakage, or drive current.
Here's a list I found some time ago (most of the comments are not mine,
and I'm sorry I've lost the attribution, but I've updated it slightly):
DEC component cross reference / substitutions
DEC EIE
D-003, D003 1N994
D-662, D662 1N645
D-664, D664 1N3606
D-668, D668 Two 1N3606 in series
D-670, D670 1N3653
D-671, D671 1N3653
D-672, D672 1N3653
DEC 999, DEC999 MM999
DEC 1008, DEC1008 MM1008
DEC 2219, DEC2219 2N2219
2N2904 2N2118A
DEC 2904, DEC2904 2N1132
DEC 3009, DEC3009 2N3009
DEC 3009A, DEC3009A 2N3009
DEC 3009B, DEC3009B 2N3009
DEC 3500, DEC3500 2N3500
DEC 3568, DEC3568 2N3568
DEC 3634, DEC3634 2N3634
DEC 3638, DEC3638 2N3638
DEC 3639, DEC3639 2N3639
DEC 3639B, DEC3639B 2N3639
DEC 3639-2, DEC3639-2 2N3639-2
DEC 3715, DEC3715 2N3715
DEC 3790, DEC3790 2N3790
DEC 4258, DEC4258 2N4258
DEC 6531, DEC6531 MPS6531
DEC 6534, DEC6534 MPS6534
SDA-6, SDA6 2N2060
1N429 1N429 6.2V 5%
1N449 1N449 6.2V 5%
1N762 1N762 5.5V 250 ohms 5%
1/4M6.8AZ5 1N4099
1/4M2.4VAZ5 1N4370
MR2064 1N4001
MR2066 1N4003
U6A900959X 7440
MPSA05 GPSA05 (Pinout reversed)
MPSA55 GPSA55 (Pinout reversed)
Connector
1209456 AMP 61320-1
1209340 Tyco/AMP 1-480459-0
From PDP-8 maintenance manual 10-5 and RK05 prints.
Also I have found the following parts to be similar but this is not from
DEC documentation so check your particular part.
DEC 82xx is Signetics 82xx series
DEC 5xxx is Signetics SPxxx
DEC 88xx is National DS88xx series or also I think Signetics 8Txx series
DEC 97401 is also labeled a SN7401, was a selected version of that part
for low leakage current.
DEC 314, DEC314 SP314A
DEC 380, DEC380 SP380A, also DS8640 is similar
DEC 384, DEC384 SP384A
DEC 8881, DEC8881 SN7401 has same pinout but less drive, SN7439
has the drive and same pinout.
For R series repairs B Klatt said:
I've successfully used 1N4148-type diodes and 2N3904 (NPN) and
2N3906 (PNP) as general purpose substitutes in the few R-series
repairs I've made. The MPSA05 and MPSA55 were popular with
DEC designers and are still readily available.
--
Pete
Pete Turnbull