Question about printer port cards (LPT)

[K1JJ]

Hola,

I have an older 1998 HP Pavillion 233mhz computer that I use for my telescope. The tracking program runs in DOS.  It uses the 25 pin printer port for hand pad controls.

I recently blew out the motherboard printer port and replaced it with one of the newer plug and play "PCI" parallel port (LPT) cards that fit into the smaller slots. For some reason the bios does not recognize the card for the scope DOS program.

Anyway, I have one of the older parallel port cards that uses the bigger socket (16 bit?) and it works fine in DOS and is recognized by bios right away.   I need to get some of these older cards for backups. Does anyone know the name for the older card socket plugs?

The socket difference is the older one has fatter pins and the mounting bracket is mounted backwards to the newer version.

What I need is the name / nomenclature of the older style plug and play printer port card to put out an ad or look for them on ebay.

Also, if anyone has some of these older parallel port cards 1998 era I can buy, please let me know.

Hope this all makes sense.

73,
Tom, K1JJ

[w8khk]

Hello Tom,

The newer card is PCI, with the narrow traces on the smaller connector.  The older cards are "ISA", an acronym for Industry Standard Architecture.  This was used in the original PC, XT, and AT computers, and comes in a single connector (8 bit) or a double connector (16 bit) plug, with the second connector section somewhat smaller than the other.  These do have the metal strap mount in the standard configuration, and the newer PCI connectors are backwards from the original.

I am cleaning up a closet full of old PC stuff, as I have too much stuff, and not enough room for the ham stuff I have recently collected.   I will check my stash, and if I have any that are applicable to your needs, they are yours for the cost of shipping.

73,
Rick

[K1JJ]

Hello Tom,

The newer card is PCI, with the narrow traces on the smaller connector.  The older cards are "ISA", an acronym for Industry Standard Architecture.  This was used in the original PC, XT, and AT computers, and comes in a single connector (8 bit) or a double connector (16 bit) plug, with the second connector section somewhat smaller than the other.  These do have the metal strap mount in the standard configuration, and the newer PCI connectors are backwards from the original.

I am cleaning up a closet full of old PC stuff, as I have too much stuff, and not enough room for the ham stuff I have recently collected.   I will check my stash, and if I have any that are applicable to your needs, they are yours for the cost of shipping.

73,
Rick

Thanks much, Rick!

"ISA".... that's what I needed to know.

Yes, I would be very happy to get a few of those old cards if you have them. 

Too bad that I, too, cleaned out 20 years of old computers last summer and threw away a few of those cards.... sigh.  Never know when ya need them.

This older scope tracking program requires FULL access to the CPU at all times, so I can't run it in Windows.   I'm not sure why bios won't recognize the PCI, cuz it does load and work under Windows with their driver.

Anyway, ISA it will be.

Thanks, OM.

Tom, K1JJ

[W1RKW]

Tom,

What brand PCI card do you have that isn't recognized by the bios?  Maybe it needs a DOS driver on the PCI side to work under the OS.  Not sure.

I have a PCI parallel printer card you can try provided it's not the same. I'm not using it since everything I have is USB. You can try it and if it works, keep it.  If it doesn't work I'd like to hold on to it. 

[K1JJ]

Tom,

What brand PCI card do you have that isn't recognized by the bios?  Maybe it needs a DOS driver on the PCI side to work under the OS.  Not sure.

I have a PCI parallel printer card you can try provided it's not the same. I'm not using it since everything I have is USB. You can try it and if it works, keep it.  If it doesn't work I'd like to hold on to it. 

Bob,

Thanks.  I'm all set for now. I'd like to stick with the ISD cards since they are proven to work.

I just bought three on eBay for only $10 total.  We'll see what happens.

If someone sends me more, that will diversify the chances of getting one that will work - and in case another blows out... :-)

Later-

T

[W1RKW]

Tom,
My guess is  your PCI card won't necessarily be picked up by the BIOS if it isn't a bonafide plug and play card. It's sort of on the borderline when there was hardware that would work in a software environment (built in firmware) but not necessarily in a hardware environment back when plug and play was in its infancy, if that makes any sense. Reflashing the BIOS with updated firmware might do the trick but finding it, assuming that it exists would be like finding a needle in  haystack.  So no point in killing yourself over it for fixing a simple problem.  For $10 bucks and a fist full of ISA cards you're good to go.

By the way,  this DOS program  you're running to drive your scope, is it something you developed?

If not and if you're interested in developing your own BASIC programs to drive the parallel port  I have a copy of MS QuickBASIC with a bunch of info for addressing the LPT port. This has its own compiler for making *.exe and other supporting files. I think everything is small enough to email.

[K1JJ]

Bob,

The scope DOS program was developed and updated since the early 90's by Mel Bartels, a well known amateur astronomer. I've used it myself since 1995, so I'm not about to reinvent the wheel... :-)

Here's the online manual.  It's a very complex scope program -  packed with features that needs to run in DOS.   Take a quick look thru it to appreciate the depth of the software... it's free shareware.
http://www.bbastrodesigns.com/StepperDoc.html

Mel's even gives me credit near the end of the manual:    
"Tom Cathey worked with me on the encoders"


Windows is a terrible CPU hog, so tracking and generating accurate stepper pulses is possible only in DOS.

I sent the PCI cards back, so I shud be OK with the new ISD cards.

Thanks for the offer -

T

[W1RKW]

Interesting, I hit the quote button to reply and I got a whole bunch of other gibberish including your reply Tom.  I wonder if INR is aware of this little quirk. I didn't post it because it was a mess.

Anyway, if you ever want to experiment in the DOS environment and make you're own executables using BASIC I have an old version of MS Quick BASIC. It's not bad for talking to the outside whirl via the LPT port.

I created a simple digital interface for controlling a dds chip via a laptop with the intent of going QRP portable but that never materialized.  The DDS side of things worked OK fine but the transmitter side never got off the ground. One of many little projects that ended up in the trash bin.

[WA1GFZ]

Hey Tom I have a 400 MHz dell and a 133 MHz dell that both need hard drives. Both have DB25 parallel ports.
You can have both of them if that helps. Bummer I just threw away my Win95 disks last week.

[K1JJ]

OK Bob -

Yeah, I'm kinda softwared out. That DOS scope program does everythimg I need and more, so no need to add any new stuff for now. Thanks for the offer though, OM.


Frank -   Yes, pull out any ISD plug-in printer cards you have before tossing out the computers. Next time I see ya I'll gladly take them.

Over the last 15 years using parallel ports for my scope, I've blown at least six boards. Mostly from lightning strikes and some from who knows what.  I'm trying some new isolation/floating techniques to isolate the power supplies and static from the port inputs. Hope that will help.

So I need to get a few older LPT cards before they are gone for good.

BTW, I'm working on the Irb and EBS SS amps today. Hope to get something going soon with the 10mw ricebox output.
Doing your newest mods too with the cores on the coax and the temp diodes in the bias supplies.

Later -

T

[WA1GFZ]

Tom,
The Printer output is on the motherboard so no plug ins. You can have both computers if you want them. They are headed to the bone yard otherwise.
Yup I was looking at them last night also. I'm thinking of mounting erb 300 on the erb 1 KW heatsink. This will give me 1200 square inches of area so I can run class A.  Many caps to change on the erb 1kw to get it on 160.

BTW I made a output transformer mod on the erb 300 since I worked on yours. You may not need it at the low power level but if you have problems we can add some more turns to the output transformer. This helped efficiency for me. 

[K1JJ]

No problem with the borads, Frank.  I have three coming and can always order more if they work out.


I just made up some calibrated hi-current meters for the two SS amps.  I'll be able to measure efficiency once running. I'll let ya know if the eff is low and needs transformer mods.

BTW, do you remember what the Erb's 24V and 48V IC currents shud be appox? 

What drive power did we figger on from Erb to drive the class A  amp to 300 pep output?


T

[Blaine N1GTU]

if you want to try a newer machine that has pci cards try upgrading to freeDoS
http://www.freedos.org
i have actually used it to run old legacy dos apps
its kinda hard to find old dos disks these days, plus this has support for newer hardware

[WA1GFZ]

Tom,
24 VDC is the first stage running class A at just under 1 amp. I think it was around 700 ma. The drivers and final start with 1/2 amp in the driver and about 1 amp in the final. I'm thinking around 1/10 watt should drive it pretty well.  Download the FET specs or send me an email at work and I can send you the class a bias numbers for both stages. Drive will go down in class A. Don't connect EB104 till you set the operating point of erb.
You can run ERB all three stages on 24 volts and should easily make the power you need to drive the EB104.

Lightning protection start with all shielded wire. Also transorbs on each output of the printer cable. You might consider opto couplers on each lead.
Do not use the scope frame for any ground returns back to the computer.

[K1JJ]

Hi Blaine,

How ya doing, OM?

I will look into the FreeDos once this computer dies. The biggest threat appears to be the cold WX. I have two 60W bulbs running in the cabinet out there for the winter... :-0



Frank - 

I'm getting about 8 watts out of Erb into 50 ohms using 14 volts. So figger maybe 20 watts or so at 24V when I hook it up tmw.  That's sounds like a good start to drive the EB amp.

T

[WA1GFZ]

24 volts should do it for you. Then just run the bias up to get the IMD you need.  Not sure how clean that 48 volt switcher is but it came out of a mil rig. I got them from Bob Stone.