simoni@strat.Stanford.EDU (Richard Simoni) (11/30/90)
I am building an expansion daughter board for a computer, and I need access to some of the signals on the existing motherboard. All of the signals I need are found on the pins of standard DIP chips on the motherboard. No fancy surface mounting, just DIPs soldered into a 4-layer board. Now... does anyone have any good ideas on how to connect a jumper wire off of those pins? Ideally, the mechanism contacting the pins should be soldered in place, while still allowing the wire itself to be removed, as in a plug/socket arrangement. My own ideas are: 1. Place an IC socket on top of the chip with the desired signal(s), with the socket pins resting on the upper "bend" of the motherboard chip's pins. Then use a DIP jumper to get the signal(s) to the daughter board. 2. Solder some sort of header onto the desired pins. A wire with the appropriate connector for said header then carries the signal(s) to the daugther board. (Is there a type of header made for specifically this purpose?) Any and all ideas appreciated, Rich Simoni simoni@strat.stanford.edu
ftpam1@acad3.fai.alaska.edu (MUNTS PHILLIP A) (12/01/90)
In article <1990Nov30.032401.27217@cascade.Stanford.EDU>, simoni@strat.Stanford.EDU (Richard Simoni) writes... > >I am building an expansion daughter board for a computer, and I need access >to some of the signals on the existing motherboard. All of the signals I >need are found on the pins of standard DIP chips on the motherboard. No >fancy surface mounting, just DIPs soldered into a 4-layer board. Now... >does anyone have any good ideas on how to connect a jumper wire off of those >pins? Ideally, the mechanism contacting the pins should be soldered in >place, while still allowing the wire itself to be removed, as in a >plug/socket arrangement. My own ideas are: > >1. Place an IC socket on top of the chip with the desired signal(s), with the >socket pins resting on the upper "bend" of the motherboard chip's pins. >Then use a DIP jumper to get the signal(s) to the daughter board. > >2. Solder some sort of header onto the desired pins. A wire with the >appropriate connector for said header then carries the signal(s) to the >daugther board. (Is there a type of header made for specifically this >purpose?) > >Any and all ideas appreciated, > >Rich Simoni >simoni@strat.stanford.edu For testing at least, you might consider DIP clips. If you get the kind without pinheads, you can plug a single row insulation displacement connector and ribbon cable onto each side of the clip. Once upon a time many eons ago I helped install a card into a Commodore PET that included an "EZ hook" type connector to acquire a signal. If you have only a few signals you might consider this also. Not recommended for a 32-bit bus! Philip Munts N7AHL NRA Extremist, etc. University of Alaska, Fairbanks
jws@thumper.mlb.semi.harris.com (James W. Swonger) (12/03/90)
Somebody (maybe Augat) makes small single-pin sockets for insertion into PC boards. These will work well for (appropriately sized) solid wire jumpers. Another alternative is to buy some sockets like the Augat DIP sockets which have the pin completely enclosed in a metal tube (unlike the cheapies which are just folded springs) and carefully remove the pin inserts from the plastic body. Either can be soldered to the pin of the IC if you are quick and careful.
henry@zoo.toronto.edu (Henry Spencer) (12/05/90)
In article <1990Dec3.142612.304@mlb.semi.harris.com> jws@thumper.mlb.semi.harris.com (James W. Swonger) writes: >Another alternative is to buy some sockets like the Augat DIP sockets which >have the pin completely enclosed in a metal tube (unlike the cheapies which >are just folded springs) and carefully remove the pin inserts from the plastic >body. What you want are sockets with "machined contacts". Incidentally, you can get the socket pins separately, but the complete sockets may be easier to find from hobbyist sources. -- "The average pointer, statistically, |Henry Spencer at U of Toronto Zoology points somewhere in X." -Hugh Redelmeier| henry@zoo.toronto.edu utzoo!henry