If you are in need of DEC MMJ cables, I have some good news and bad news. First, the good news: http://www.amazon.com/Flat-Modular-Cable-RJ12-6x6MMJ/dp/B000AA2SL4?ie=UTF8&p... <http://www.amazon.com/Flat-Modular-Cable-RJ12-6x6MMJ/dp/B000AA2SL4?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00> The picture is definitely an offset key (MMJ) six strand cable, 7 feet long, for only $3.92. The bad news… It’s not actually an MMJ, it’s just a regular MJ (Modular Jack). Even so, there’s still good news. With some strategic dremeling it is completely possible to trim one side of the MJ down so that it will fit quite well into a DEC MMJ socket. :)
Dave, I think several folks have the crimp tools and jacks/plugs needed to make MMJ leads. The problem I have had is finding 9 or 25-pin adaptors when I want to plug into a non-DEC terminal. The last cables I made were "bodged" from a similar cable. I cut one RJ12 off and replaced it with an MMJ plug, so I ended up with an MMJ<->RJ12 lead. I then tweaked an RJ12 DE-9 Socket to connect to a laptop with serial port. In fact these leads are a cheap source 6-Way cable... Dave
-----Original Message----- From: vcf-midatlantic [mailto:vcf-midatlantic- bounces@lists.vintagecomputerfederation.org] On Behalf Of David Hoelzer via vcf-midatlantic Sent: 23 April 2016 19:32 To: vcf-midatlantic <vcf-midatlantic@lists.vintagecomputerfederation.org> Cc: David Hoelzer <dhoelzer@enclaveforensics.com> Subject: [vcf-midatlantic] MMJ cables for cheap
If you are in need of DEC MMJ cables, I have some good news and bad news. First, the good news:
http://www.amazon.com/Flat-Modular-Cable-RJ12- 6x6MMJ/dp/B000AA2SL4?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailp age_o03_s00 <http://www.amazon.com/Flat-Modular-Cable-RJ12- 6x6MMJ/dp/B000AA2SL4?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailp age_o03_s00>
The picture is definitely an offset key (MMJ) six strand cable, 7 feet long, for only $3.92.
The bad news… It’s not actually an MMJ, it’s just a regular MJ (Modular Jack). Even so, there’s still good news. With some strategic dremeling it is completely possible to trim one side of the MJ down so that it will fit quite well into a DEC MMJ socket. :)
On Apr 23, 2016, at 3:11 PM, Dave Wade via vcf-midatlantic <vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
Dave,
I think several folks have the crimp tools and jacks/plugs needed to make MMJ leads. The problem I have had is finding 9 or 25-pin adaptors when I want to plug into a non-DEC terminal. The last cables I made were "bodged" from a similar cable. I cut one RJ12 off and replaced it with an MMJ plug, so I ended up with an MMJ<->RJ12 lead. I then tweaked an RJ12 DE-9 Socket to connect to a laptop with serial port. In fact these leads are a cheap source 6-Way cable...
DE9 and DB25 to 8p8c adaptors with completely customizable pin selections are easily available from Monoprice, though they insist on calling them DB9 and RJ45 (you really DON'T want actual RJ45 going into your motherboard; those buffers are tolerant, but 50v is a lot): http://www.monoprice.com/product?p_id=1152 <http://www.monoprice.com/product?p_id=1152> http://www.monoprice.com/product?p_id=1159 <http://www.monoprice.com/product?p_id=1159> Despite what it looks like in the picture, it comes with the pins uninserted into the D-sub socket, so you can pin them out however you like. I like to pin mine out to the Cyclades specification, for two reasons: 1) I have a big Cyclades terminal server, so it's handy to be able to be able to move the cables between the two, and 2) it's actually a mostly 1-to-1 match for the MMJ pinout; you only have to bend down/snip one wire, and nothing has to cross over. A Paladin crimp frame and the MMJ and 8p8c dies will set you back probably $80-$100 all told, but if you ever have plans to make even just Ethernet cables in the future, it's a really good thing to have. The MMJ end plugs are pretty cheap in bulk (about 30 cents each) and still readily available; ask around on the list, and I'm sure you'll find people willing to split a bag of 100. Making 8p8c->MMJ cables is really the best way to go, especially with the presence of these little D-sub adaptors. - Dave
Those are super, but I have DEC gear with MMJ sockets.. I also have a stack of DB9-MMJ converters from when I owned Alphas too.
On Apr 23, 2016, at 4:33 PM, David Riley via vcf-midatlantic <vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
On Apr 23, 2016, at 3:11 PM, Dave Wade via vcf-midatlantic <vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
Dave,
I think several folks have the crimp tools and jacks/plugs needed to make MMJ leads. The problem I have had is finding 9 or 25-pin adaptors when I want to plug into a non-DEC terminal. The last cables I made were "bodged" from a similar cable. I cut one RJ12 off and replaced it with an MMJ plug, so I ended up with an MMJ<->RJ12 lead. I then tweaked an RJ12 DE-9 Socket to connect to a laptop with serial port. In fact these leads are a cheap source 6-Way cable...
DE9 and DB25 to 8p8c adaptors with completely customizable pin selections are easily available from Monoprice, though they insist on calling them DB9 and RJ45 (you really DON'T want actual RJ45 going into your motherboard; those buffers are tolerant, but 50v is a lot):
http://www.monoprice.com/product?p_id=1152 <http://www.monoprice.com/product?p_id=1152> http://www.monoprice.com/product?p_id=1159 <http://www.monoprice.com/product?p_id=1159>
Despite what it looks like in the picture, it comes with the pins uninserted into the D-sub socket, so you can pin them out however you like. I like to pin mine out to the Cyclades specification, for two reasons: 1) I have a big Cyclades terminal server, so it's handy to be able to be able to move the cables between the two, and 2) it's actually a mostly 1-to-1 match for the MMJ pinout; you only have to bend down/snip one wire, and nothing has to cross over. A Paladin crimp frame and the MMJ and 8p8c dies will set you back probably $80-$100 all told, but if you ever have plans to make even just Ethernet cables in the future, it's a really good thing to have. The MMJ end plugs are pretty cheap in bulk (about 30 cents each) and still readily available; ask around on the list, and I'm sure you'll find people willing to split a bag of 100.
Making 8p8c->MMJ cables is really the best way to go, especially with the presence of these little D-sub adaptors.
- Dave
On Apr 23, 2016, at 18:29, David Hoelzer <dhoelzer@enclaveforensics.com> wrote:
Those are super, but I have DEC gear with MMJ sockets.. I also have a stack of DB9-MMJ converters from when I owned Alphas too.
I have lots of DEC gear with MMJ sockets as well; it's almost exclusively what I use these for, with MMJ->8p8c cables to connect them. But as I said, I also have a big 48-port terminal server that also uses the same 8p8c pinout, so I guess it's more a matter of convenience for me (that, and I hadn't found the MMJ->DE9 converters at a reasonable price; thanks, VAXman!). If you have lots of other serial equipment that uses 8p8c (very popular for Cyclades, Sun, Cisco, others), those cables can be VERY handy. - Dave
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David Riley