Date   
Re: National Instruments GPIB-400

Arie de Muijnck
 

On 2019-10-01 23:12, Reginald Beardsley via Groups.Io wrote:


FWIW There is an entire EEVblog thread on the AR488 FW which is based on
an Arduino Uno, but expanding to support the Mega 256, STM32F103, and
others. Now that the author has completed a major update on the FW to
simplify customization I'm going to add a number of features to control
external relays, read a temperature and humidity sensor, real time clock
and feed a strobe signal to synchronize measurements with the 34401As.
Thanks for that AR488 info, that looks really good.
I was searching for a low cost USB-GPIB adapter.

BTW, did anyone ever buy this (looks new on aliexpress),
it's a compact open source Prologic compatible for about $20:
https://www.aliexpress.com/item/4000034884174.html
The open source is here:
https://github.com/fenrir-naru/gpib-usbcdc

( https://github.com/fenrir-naru/gpib-usbcdc )

Regards,
Arie de Muijnck


Re: National Instruments GPIB-400

Arie de Muijnck
 

On 2019-10-01 23:12, Reginald Beardsley via Groups.Io wrote:


FWIW There is an entire EEVblog thread on the AR488 FW which is based on
an Arduino Uno, but expanding to support the Mega 256, STM32F103, and
others. Now that the author has completed a major update on the FW to
simplify customization I'm going to add a number of features to control
external relays, read a temperature and humidity sensor, real time clock
and feed a strobe signal to synchronize measurements with the 34401As.
Thanks for that AR488 link, I'm also looking for an affordable USB-GPIB adapter.

BTW: did anyone use this? It seems new on AliExpress, a EUR 18 clone from an opensource project:
https://www.aliexpress.com/item/4000034884174.html
( https://www.aliexpress.com/item/4000034884174.html ) https://github.com/fenrir-naru/gpib-usbcdc

Regards,
Arie

Re: National Instruments GPIB-400

Arie de Muijnck
 

Thanks for that AR488 info, that looks really good.
I was searching for a low cost USB-GPIB adapter.

BTW, did anyone ever buy this (looks new on aliexpress),
it's a compact open source Prologic compatible for about $20:
https://www.aliexpress.com/item/4000034884174.html
The open source is here:
https://github.com/fenrir-naru/gpib-usbcdc

Regards,
Arie de Muijnck

Re: Sanity check- is the TM500 interface spacing .150" or .156"?

EJP
 

It is JAMMA, but they only make the card. The extender is a kit vended by someone else.

Re: TM5006A manual

Phil
 

Thank you David !
I bought it already from Artek, and had it immediately delivered because over FTP, which made sense as I live in Europe, so no shipping time/cost.
Just looked at the Qservice website and discovered they have many spare parts that will prove invaluable at some point for restorations I have waiting in the backlog.

regards,
-Phil

Re: Icom IC 720A

Clive Redfern
 

Thanks for the prompt response John.I like working on equipment that has components that are large enough to see!
73Clive

Re: Icom IC 720A

John Stoole
 

Thanks Alex for the prompt reply...all the display voltages appear to be fine, and I do notice as I power OFF the display flashes all it digit's with " 8 " but as soon as I power ON nothing just a blank screen, I am not expert when it comes to all these digital circuits, more at hone with the old tubes !!!! 83 years old now and you cant teach an old dog new tricks !! Keep an ear to the ground for me maybe somebody is breaking an old 720A and I can get a replacement Logic Board
Many Thanks
John mi0dfg

Re: Icom IC 720A

John Stoole
 

Hello Clive thanks for your suggestions, as for the rotary relay replacement in the LPF, I followed the very excellent Article by KA6BFB at


http://tinkyr.altervista.org/radio/projects/Icom%20720A%20rotary%20relay%20replacement.pdf
Very simple and works perfectly
73
John

ebay 7104 arrived :-)

Reginald Beardsley
 

It came today. It was very carefully packed with a layer of bubble wrap and 1" hard foam. FedEx handled it very carefully. There were no dings on the box from dropping it.

I just made initial tests using one of Leo's pulsers. Left channel is 350 ps rise time, right channel is about 500 ps. Both clearly need adjustment to be at their best, but as received still very good. And as much work as adjusting the 465 attenuators was, I'd expect that the 7A29s will be take even more time to get optimal performance.

I want a full Tek manual set for it just in case anyone has any spare manuals, 7104, 7A29, 7B15 & 7B10.

Now, where will I put it.......

Have Fun!
Reg

Re: Icom IC 720A

Clive Redfern
 

Hi John,Replace the electrolytics around the display supply.The modern replacements are smaller and take higher V and °C for similar footprint.(I've replaced all the C's in my old Icom txrs - not just the display related ones.)
If you find frequency stability problems then replace PLL plastic trimmers with ceramic - you'll find a lot of data online/youtube.
Caps - Icoms' Achilles' heel. Unfair I suppose - capacitors are a weak link everywhere.
How did you replace the rotary switch?I'm interested for my IC701
Clive F5VHS

On Wednesday, October 2, 2019, 01:35:15 PM GMT + 2, John Stoole <john@...> wrote:

Greetings All, I have an IC 720A that I am restoring, it is now operating TX and RX and I have also done the modification to the LPF to get rid of the "clacking" rotary
relay, and now have silent band switching. The only problem is no display, it is quite possible that the problem is in the Logic board possibly the Display Driver (uPD549c). So I was wondering if I could get a Logic board, it would be a great thing to give up this 100% serviceable, resprayed and looking great.
Any help would be greatly appreciated.
John
mi0dfg (N.Ireland)

Re: National Instruments GPIB-400 - TMS9914 source 9.00

Harvey White
 

Thanks, I've got enough 9914's (due to the DM5010 rebuilding project, leaky nicad, messy.....) to redo all three that I have, assuming that they're not damaged.  The same design (a plug in extension to a 4x4 CPU board, shaped to duplicate the CPU's 488 connector fingers), allows a CB7210.2 to be plugged in.

Unless you've got a good and dependable supply of 9914's to make available, I'll try what I have, and even then I'll likely go the FPGA route.  OpenCores.org has at least one in VHDL that I can easily adapt and plug into my register structure (modular...). Even then, while the FPGA is more expensive, it's far more versatile, and the 9914 isn't a controller, which I'd want.  I've got working software for the CB7210, including the instrument definition structures and commands.  All it needs is to be rewritten from C to C++.

For the DM5010 rebuild, I'll be using the 9914.  For a controller, the CB7210.  For a universal design, I'll just put in the FPGA and experiment with that.

My current board design uses the 40 pin dips, and if I go redesign the board to use the FPGA, I might as well redesign the CPU a bit.  I can eliminate the FPGA that substitutes for the 8279 front panel controller (do it differently), etc, etc.

So I think I'll decline your kind offer, at least for now, but thanks anyway.

Harvey

On 10/2/2019 11:35 AM, Jeff Kruth via Groups.Io wrote:
I have the PLCC version of the 9914 chip for 9.00 if your boards can use it.


J. KruthIn a message dated 10/2/2019 11:00:22 AM Eastern Standard Time, madyn@... writes:

On 10/2/2019 10:36 AM, George Kerber wrote:
  I believe the TMS9914A 40-pin dip package is available from NI under part
number NAT9914BPD. They are $187 for a tube of 9 chips.
And there we have a slight problem.  187 USD is not something I'd want
to lay out just because.  20 dollars or so per chip puts the 11 dollar
FPGA at a significant cost advantage, and with the FPGA, I can add
whatever features I want.  It would be a Xilinx Spartan 6-LX4 in a 144
pin TQFP package, very workable.  (and I can buy one chip at a time
should I care to do so).

If there's enough room in that for an SPI interface, multiple registers,
LED controllers, Neopixel sequencer, serial FIFOs, and the uart that
goes with them, I can't see the 488 code not fitting....

At that price, it would be economically feasible (but not morally so) to
buy defunct TMS5000 plugins, grab the 488 bus components, and use the
rest as spare parts.  Not a pleasant course of action, though, so I'd
opt for lower cost.

Just checked Mouser, and none of the older chips are available.

The CPU module for the DM5010, with a few modifications, might make an
interesting WIFI enabled 488 bus interface for a TM5000 system.....
Hmmmmmm.


Harvey


see NI NAT9914 Series - National Instruments
<http://sine.ni.com/nips/cds/view/p/lang/en/nid/11153#productlisting>

On Tue, Oct 1, 2019 at 10:05 PM Harvey White <madyn@...> wrote:

On 10/1/2019 5:39 PM, Bob Albert via Groups.Io wrote:
    Thanks Harvey!  That shows clearly that building one or two of these
isn't a trivial matter.

Not trivial, but quite doable....

The real problem is not so much the software, that can be written easily
enough depending on your skill level, it's the 488 bus controller
itself.  The TMS9914 and CB7210 are not readily available, although I do
have enough for a board or so.  The 68488 is not a controller, which
limits it.  If I were to go from scratch, and wanted to do the design
more or less properly (and apologies to those who have taken the simpler
route), I'd be designing for function and not necessarily cost.  It
wouldn't be a product.  I'd use the appropriate (still available)
drivers, an FPGA at about 11 dollars or so, I'd likely use an STMicro
LK432 processor in the arduino nano format.  That gives me the USB input
if I want to go that way, if not, then the Chinese made CH340 adaptors
are inexpensive and go USB to TTL level serial.  The LK432 processor is
likely far more than is needed, but I have a considerable infrastructure
developed for ARM processors.

Having said that, it would seem that economics of scale ought to chop a
bunch off the costs.  If it costs $40 to build one, then it should cost $40
to buy ten of them if they are cranked out in quantity.  This is proven
time after time online with great stuff at what appears to be practically
giveaway prices.

Note all the stuff that I said was "free".  Software development time,
assembly time, and so on....


So my take on it remains to wait and see if the magic appears on this
item.  And if not, I have plenty to keep my interests going at more than
full blast.  My list of unfinished projects is daunting.  I need a reason
to get at one or two of them at least.

I understand about unfinished projects, they all take time and some
money.  I have an assortment of 488 capable test equipment, so I do have
a need for a 488 controller.


  From the antenna rotator to the synthesized signal generator to the VNA
to the chart recorder and so on.  And someone is on the way to bring me
some gear to repair.
I love this stuff!
Can't disagree.  Finished redesigning the FPGA for a modular test
equipment monitoring design similar to a tricorder.  The FPGA handles
LEDS, bidirectional I/O, neopixels, distance sensing, and serial/FIFO
for the WIFI.  Still working on parts of it, but I went *very* modular
with the VHDL.  Now that I have two versions (close to each other), it's
time to go back to RF networking.

Harvey


Bob
      On Tuesday, October 1, 2019, 02:17:43 PM PDT, Harvey White <
madyn@...> wrote:
On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
    Correct me if I am wrong, but it seems that the cables we are
discussing are little more than some wire and a couple of connectors.
Perhaps there is some electronics in there as well; I suspect so.  But
isn't it maybe just level shifting?
Actually, it's a bit more than that.  You have at least several
subsections.  Firstly, you have I/O drivers, getting the right ones is
important for driving more loads.  Next, you have the 488 chip itself.
I know of three of them that are specific controllers, and there's an
FPGA implementation out there somewhere.  FPGA of the right size may be
5 to 15 dollars.  Next, you need a USB to something interface, likely to
TTL serial data. You'd also (with at least the non FPGA versions, want a
processor to implement the conversion from the serial data to the
chip/FPGA.  Throw in 3 to 7 dollars for that.  Ask at least a dollar
fifty per PC board (and that's Chinese special, no bigger than 100mm
square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff,
and 7 for major stuff like processors, and USB interfaces. Throw in
another five dollars for miscellaneous chips, ignore the connector,and
ignore the labor to put it together, and we've got 32 dollars and then
some.
Buy in quantity, fake some chips, you're lots cheaper.  Throw in
assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is
ridiculous.  I can buy USB devices that can read many memory card formats
for a couple of dollars, and I suspect those aren't any simpler than a GPIB
interface cable.  I can buy the nanoVNA for less than $50.  So the cost of
the interface is definitely out of line.
Yes there are companies that buy things regardless of price.  The
manufacturers have probably analyzed the market and have decided that it's
better to sell a few at high prices than many at lower prices.  It's their
call and I am not in a position to argue.  But I vote with my money and my
money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of
the market.  Value is important to me, if not to the big guys who do this
stuff for a living (of which I used to be a part).
Bob
        On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <
leo@...> wrote:
    On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of
the
GPIB-USB-HS adapters come with a CD containing driver versions that
will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo














Re: Sanity check- is the TM500 interface spacing .150" or .156"?

Dave Seiter
 

JAMA maybe?  I remember them, but haven't them in a long time.  
Anyway, the extender worked the second time.  
-Dave

On Monday, September 30, 2019, 03:21:41 AM PDT, Alexandre Souza <alexandre.tabajara@...> wrote:

JAMMA is an arcade machine connector standard, not a manufacturer =D

---8<---Corte aqui---8<---
http://www.tabajara-labs.blogspot.com
http://www.tabalabs.com.br
---8<---Corte aqui---8<---


Em seg, 30 de set de 2019 às 05:39, Albert Otten <aodiversen@...>
escreveu:

Jamma makes (or made) kits for TM500 extension cables. A Google search for
"jamma boards connector TM500" will immediately show you 3.96mm/0.156" .

Albert



Re: National Instruments GPIB-400 - TMS9914 source 9.00

Jeff Kruth
 

I have the PLCC version of the 9914 chip for 9.00 if your boards can use it.


J. KruthIn a message dated 10/2/2019 11:00:22 AM Eastern Standard Time, madyn@... writes:

On 10/2/2019 10:36 AM, George Kerber wrote:
  I believe the TMS9914A 40-pin dip package is available from NI under part
number NAT9914BPD. They are $187 for a tube of 9 chips.
And there we have a slight problem.  187 USD is not something I'd want
to lay out just because.  20 dollars or so per chip puts the 11 dollar
FPGA at a significant cost advantage, and with the FPGA, I can add
whatever features I want.  It would be a Xilinx Spartan 6-LX4 in a 144
pin TQFP package, very workable.  (and I can buy one chip at a time
should I care to do so).

If there's enough room in that for an SPI interface, multiple registers,
LED controllers, Neopixel sequencer, serial FIFOs, and the uart that
goes with them, I can't see the 488 code not fitting....

At that price, it would be economically feasible (but not morally so) to
buy defunct TMS5000 plugins, grab the 488 bus components, and use the
rest as spare parts.  Not a pleasant course of action, though, so I'd
opt for lower cost.

Just checked Mouser, and none of the older chips are available.

The CPU module for the DM5010, with a few modifications, might make an
interesting WIFI enabled 488 bus interface for a TM5000 system..... 
Hmmmmmm.


Harvey


see NI NAT9914 Series - National Instruments
<http://sine.ni.com/nips/cds/view/p/lang/en/nid/11153#productlisting>

On Tue, Oct 1, 2019 at 10:05 PM Harvey White <madyn@...> wrote:

On 10/1/2019 5:39 PM, Bob Albert via Groups.Io wrote:
    Thanks Harvey!  That shows clearly that building one or two of these
isn't a trivial matter.

Not trivial, but quite doable....

The real problem is not so much the software, that can be written easily
enough depending on your skill level, it's the 488 bus controller
itself.  The TMS9914 and CB7210 are not readily available, although I do
have enough for a board or so.  The 68488 is not a controller, which
limits it.  If I were to go from scratch, and wanted to do the design
more or less properly (and apologies to those who have taken the simpler
route), I'd be designing for function and not necessarily cost.  It
wouldn't be a product.  I'd use the appropriate (still available)
drivers, an FPGA at about 11 dollars or so, I'd likely use an STMicro
LK432 processor in the arduino nano format.  That gives me the USB input
if I want to go that way, if not, then the Chinese made CH340 adaptors
are inexpensive and go USB to TTL level serial.  The LK432 processor is
likely far more than is needed, but I have a considerable infrastructure
developed for ARM processors.

Having said that, it would seem that economics of scale ought to chop a
bunch off the costs.  If it costs $40 to build one, then it should cost $40
to buy ten of them if they are cranked out in quantity.  This is proven
time after time online with great stuff at what appears to be practically
giveaway prices.

Note all the stuff that I said was "free".  Software development time,
assembly time, and so on....


So my take on it remains to wait and see if the magic appears on this
item.  And if not, I have plenty to keep my interests going at more than
full blast.  My list of unfinished projects is daunting.  I need a reason
to get at one or two of them at least.

I understand about unfinished projects, they all take time and some
money.  I have an assortment of 488 capable test equipment, so I do have
a need for a 488 controller.


  From the antenna rotator to the synthesized signal generator to the VNA
to the chart recorder and so on.  And someone is on the way to bring me
some gear to repair.
I love this stuff!
Can't disagree.  Finished redesigning the FPGA for a modular test
equipment monitoring design similar to a tricorder.  The FPGA handles
LEDS, bidirectional I/O, neopixels, distance sensing, and serial/FIFO
for the WIFI.  Still working on parts of it, but I went *very* modular
with the VHDL.  Now that I have two versions (close to each other), it's
time to go back to RF networking.

Harvey


Bob
      On Tuesday, October 1, 2019, 02:17:43 PM PDT, Harvey White <
madyn@...> wrote:

On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
    Correct me if I am wrong, but it seems that the cables we are
discussing are little more than some wire and a couple of connectors.
Perhaps there is some electronics in there as well; I suspect so.  But
isn't it maybe just level shifting?
Actually, it's a bit more than that.  You have at least several
subsections.  Firstly, you have I/O drivers, getting the right ones is
important for driving more loads.  Next, you have the 488 chip itself.
I know of three of them that are specific controllers, and there's an
FPGA implementation out there somewhere.  FPGA of the right size may be
5 to 15 dollars.  Next, you need a USB to something interface, likely to
TTL serial data. You'd also (with at least the non FPGA versions, want a
processor to implement the conversion from the serial data to the
chip/FPGA.  Throw in 3 to 7 dollars for that.  Ask at least a dollar
fifty per PC board (and that's Chinese special, no bigger than 100mm
square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff,
and 7 for major stuff like processors, and USB interfaces. Throw in
another five dollars for miscellaneous chips, ignore the connector,and
ignore the labor to put it together, and we've got 32 dollars and then
some.
Buy in quantity, fake some chips, you're lots cheaper.  Throw in
assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is
ridiculous.  I can buy USB devices that can read many memory card formats
for a couple of dollars, and I suspect those aren't any simpler than a GPIB
interface cable.  I can buy the nanoVNA for less than $50.  So the cost of
the interface is definitely out of line.
Yes there are companies that buy things regardless of price.  The
manufacturers have probably analyzed the market and have decided that it's
better to sell a few at high prices than many at lower prices.  It's their
call and I am not in a position to argue.  But I vote with my money and my
money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of
the market.  Value is important to me, if not to the big guys who do this
stuff for a living (of which I used to be a part).
Bob
        On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <
leo@...> wrote:
    On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of
the
GPIB-USB-HS adapters come with a CD containing driver versions that
will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo













Re: National Instruments GPIB-400

Harvey White
 

On 10/2/2019 10:36 AM, George Kerber wrote:
I believe the TMS9914A 40-pin dip package is available from NI under part
number NAT9914BPD. They are $187 for a tube of 9 chips.
And there we have a slight problem.  187 USD is not something I'd want to lay out just because.  20 dollars or so per chip puts the 11 dollar FPGA at a significant cost advantage, and with the FPGA, I can add whatever features I want.  It would be a Xilinx Spartan 6-LX4 in a 144 pin TQFP package, very workable.  (and I can buy one chip at a time should I care to do so).

If there's enough room in that for an SPI interface, multiple registers, LED controllers, Neopixel sequencer, serial FIFOs, and the uart that goes with them, I can't see the 488 code not fitting....

At that price, it would be economically feasible (but not morally so) to buy defunct TMS5000 plugins, grab the 488 bus components, and use the rest as spare parts.  Not a pleasant course of action, though, so I'd opt for lower cost.

Just checked Mouser, and none of the older chips are available.

The CPU module for the DM5010, with a few modifications, might make an interesting WIFI enabled 488 bus interface for a TM5000 system.....  Hmmmmmm.


Harvey


see NI NAT9914 Series - National Instruments
<http://sine.ni.com/nips/cds/view/p/lang/en/nid/11153#productlisting>

On Tue, Oct 1, 2019 at 10:05 PM Harvey White <madyn@...> wrote:

On 10/1/2019 5:39 PM, Bob Albert via Groups.Io wrote:
Thanks Harvey! That shows clearly that building one or two of these
isn't a trivial matter.

Not trivial, but quite doable....

The real problem is not so much the software, that can be written easily
enough depending on your skill level, it's the 488 bus controller
itself. The TMS9914 and CB7210 are not readily available, although I do
have enough for a board or so. The 68488 is not a controller, which
limits it. If I were to go from scratch, and wanted to do the design
more or less properly (and apologies to those who have taken the simpler
route), I'd be designing for function and not necessarily cost. It
wouldn't be a product. I'd use the appropriate (still available)
drivers, an FPGA at about 11 dollars or so, I'd likely use an STMicro
LK432 processor in the arduino nano format. That gives me the USB input
if I want to go that way, if not, then the Chinese made CH340 adaptors
are inexpensive and go USB to TTL level serial. The LK432 processor is
likely far more than is needed, but I have a considerable infrastructure
developed for ARM processors.

Having said that, it would seem that economics of scale ought to chop a
bunch off the costs. If it costs $40 to build one, then it should cost $40
to buy ten of them if they are cranked out in quantity. This is proven
time after time online with great stuff at what appears to be practically
giveaway prices.

Note all the stuff that I said was "free". Software development time,
assembly time, and so on....


So my take on it remains to wait and see if the magic appears on this
item. And if not, I have plenty to keep my interests going at more than
full blast. My list of unfinished projects is daunting. I need a reason
to get at one or two of them at least.

I understand about unfinished projects, they all take time and some
money. I have an assortment of 488 capable test equipment, so I do have
a need for a 488 controller.


From the antenna rotator to the synthesized signal generator to the VNA
to the chart recorder and so on. And someone is on the way to bring me
some gear to repair.
I love this stuff!
Can't disagree. Finished redesigning the FPGA for a modular test
equipment monitoring design similar to a tricorder. The FPGA handles
LEDS, bidirectional I/O, neopixels, distance sensing, and serial/FIFO
for the WIFI. Still working on parts of it, but I went *very* modular
with the VHDL. Now that I have two versions (close to each other), it's
time to go back to RF networking.

Harvey


Bob
On Tuesday, October 1, 2019, 02:17:43 PM PDT, Harvey White <
madyn@...> wrote:

On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
Correct me if I am wrong, but it seems that the cables we are
discussing are little more than some wire and a couple of connectors.
Perhaps there is some electronics in there as well; I suspect so. But
isn't it maybe just level shifting?
Actually, it's a bit more than that. You have at least several
subsections. Firstly, you have I/O drivers, getting the right ones is
important for driving more loads. Next, you have the 488 chip itself.
I know of three of them that are specific controllers, and there's an
FPGA implementation out there somewhere. FPGA of the right size may be
5 to 15 dollars. Next, you need a USB to something interface, likely to
TTL serial data. You'd also (with at least the non FPGA versions, want a
processor to implement the conversion from the serial data to the
chip/FPGA. Throw in 3 to 7 dollars for that. Ask at least a dollar
fifty per PC board (and that's Chinese special, no bigger than 100mm
square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff,
and 7 for major stuff like processors, and USB interfaces. Throw in
another five dollars for miscellaneous chips, ignore the connector,and
ignore the labor to put it together, and we've got 32 dollars and then
some.
Buy in quantity, fake some chips, you're lots cheaper. Throw in
assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is
ridiculous. I can buy USB devices that can read many memory card formats
for a couple of dollars, and I suspect those aren't any simpler than a GPIB
interface cable. I can buy the nanoVNA for less than $50. So the cost of
the interface is definitely out of line.
Yes there are companies that buy things regardless of price. The
manufacturers have probably analyzed the market and have decided that it's
better to sell a few at high prices than many at lower prices. It's their
call and I am not in a position to argue. But I vote with my money and my
money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of
the market. Value is important to me, if not to the big guys who do this
stuff for a living (of which I used to be a part).
Bob
On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <
leo@...> wrote:
On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of
the
GPIB-USB-HS adapters come with a CD containing driver versions that
will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo












Re: National Instruments GPIB-400

Jeff Kruth
 

I have the PLCC version of the 9914 if people can lay out their boards for it. These are NOS from a manufacturer I bought out.  Need only to buy 1 not 9 and cheaper!


Jeff Kruth

In a message dated 10/2/2019 10:37:03 AM Eastern Standard Time, gk5220@... writes:
I believe the TMS9914A 40-pin dip package is available from NI under part
number NAT9914BPD. They are $187 for a tube of 9 chips.
see NI NAT9914 Series - National Instruments
<http://sine.ni.com/nips/cds/view/p/lang/en/nid/11153#productlisting>

On Tue, Oct 1, 2019 at 10:05 PM Harvey White <madyn@...> wrote:


On 10/1/2019 5:39 PM, Bob Albert via Groups.Io wrote:
  Thanks Harvey!  That shows clearly that building one or two of these
isn't a trivial matter.

Not trivial, but quite doable....

The real problem is not so much the software, that can be written easily
enough depending on your skill level, it's the 488 bus controller
itself.  The TMS9914 and CB7210 are not readily available, although I do
have enough for a board or so.  The 68488 is not a controller, which
limits it.  If I were to go from scratch, and wanted to do the design
more or less properly (and apologies to those who have taken the simpler
route), I'd be designing for function and not necessarily cost.  It
wouldn't be a product.  I'd use the appropriate (still available)
drivers, an FPGA at about 11 dollars or so, I'd likely use an STMicro
LK432 processor in the arduino nano format.  That gives me the USB input
if I want to go that way, if not, then the Chinese made CH340 adaptors
are inexpensive and go USB to TTL level serial.  The LK432 processor is
likely far more than is needed, but I have a considerable infrastructure
developed for ARM processors.

Having said that, it would seem that economics of scale ought to chop a
bunch off the costs.  If it costs $40 to build one, then it should cost $40
to buy ten of them if they are cranked out in quantity.  This is proven
time after time online with great stuff at what appears to be practically
giveaway prices.

Note all the stuff that I said was "free".  Software development time,
assembly time, and so on....


So my take on it remains to wait and see if the magic appears on this
item.  And if not, I have plenty to keep my interests going at more than
full blast.  My list of unfinished projects is daunting.  I need a reason
to get at one or two of them at least.

I understand about unfinished projects, they all take time and some
money.  I have an assortment of 488 capable test equipment, so I do have
a need for a 488 controller.


  From the antenna rotator to the synthesized signal generator to the VNA
to the chart recorder and so on.  And someone is on the way to bring me
some gear to repair.
I love this stuff!
Can't disagree.  Finished redesigning the FPGA for a modular test
equipment monitoring design similar to a tricorder.  The FPGA handles
LEDS, bidirectional I/O, neopixels, distance sensing, and serial/FIFO
for the WIFI.  Still working on parts of it, but I went *very* modular
with the VHDL.  Now that I have two versions (close to each other), it's
time to go back to RF networking.

Harvey


Bob
      On Tuesday, October 1, 2019, 02:17:43 PM PDT, Harvey White <
madyn@...> wrote:


On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
    Correct me if I am wrong, but it seems that the cables we are
discussing are little more than some wire and a couple of connectors.
Perhaps there is some electronics in there as well; I suspect so.  But
isn't it maybe just level shifting?
Actually, it's a bit more than that.  You have at least several
subsections.  Firstly, you have I/O drivers, getting the right ones is
important for driving more loads.  Next, you have the 488 chip itself.
I know of three of them that are specific controllers, and there's an
FPGA implementation out there somewhere.  FPGA of the right size may be
5 to 15 dollars.  Next, you need a USB to something interface, likely to
TTL serial data. You'd also (with at least the non FPGA versions, want a
processor to implement the conversion from the serial data to the
chip/FPGA.  Throw in 3 to 7 dollars for that.  Ask at least a dollar
fifty per PC board (and that's Chinese special, no bigger than 100mm
square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff,
and 7 for major stuff like processors, and USB interfaces. Throw in
another five dollars for miscellaneous chips, ignore the connector,and
ignore the labor to put it together, and we've got 32 dollars and then
some.

Buy in quantity, fake some chips, you're lots cheaper.  Throw in
assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is
ridiculous.  I can buy USB devices that can read many memory card formats
for a couple of dollars, and I suspect those aren't any simpler than a GPIB
interface cable.  I can buy the nanoVNA for less than $50.  So the cost of
the interface is definitely out of line.
Yes there are companies that buy things regardless of price.  The
manufacturers have probably analyzed the market and have decided that it's
better to sell a few at high prices than many at lower prices.  It's their
call and I am not in a position to argue.  But I vote with my money and my
money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of
the market.  Value is important to me, if not to the big guys who do this
stuff for a living (of which I used to be a part).
Bob
        On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <
leo@...> wrote:

    On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of
the
GPIB-USB-HS adapters come with a CD containing driver versions that
will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo













Re: National Instruments GPIB-400

George Kerber
 

I believe the TMS9914A 40-pin dip package is available from NI under part
number NAT9914BPD. They are $187 for a tube of 9 chips.
see NI NAT9914 Series - National Instruments
<http://sine.ni.com/nips/cds/view/p/lang/en/nid/11153#productlisting>

On Tue, Oct 1, 2019 at 10:05 PM Harvey White <madyn@...> wrote:


On 10/1/2019 5:39 PM, Bob Albert via Groups.Io wrote:
Thanks Harvey! That shows clearly that building one or two of these
isn't a trivial matter.

Not trivial, but quite doable....

The real problem is not so much the software, that can be written easily
enough depending on your skill level, it's the 488 bus controller
itself. The TMS9914 and CB7210 are not readily available, although I do
have enough for a board or so. The 68488 is not a controller, which
limits it. If I were to go from scratch, and wanted to do the design
more or less properly (and apologies to those who have taken the simpler
route), I'd be designing for function and not necessarily cost. It
wouldn't be a product. I'd use the appropriate (still available)
drivers, an FPGA at about 11 dollars or so, I'd likely use an STMicro
LK432 processor in the arduino nano format. That gives me the USB input
if I want to go that way, if not, then the Chinese made CH340 adaptors
are inexpensive and go USB to TTL level serial. The LK432 processor is
likely far more than is needed, but I have a considerable infrastructure
developed for ARM processors.

Having said that, it would seem that economics of scale ought to chop a
bunch off the costs. If it costs $40 to build one, then it should cost $40
to buy ten of them if they are cranked out in quantity. This is proven
time after time online with great stuff at what appears to be practically
giveaway prices.

Note all the stuff that I said was "free". Software development time,
assembly time, and so on....


So my take on it remains to wait and see if the magic appears on this
item. And if not, I have plenty to keep my interests going at more than
full blast. My list of unfinished projects is daunting. I need a reason
to get at one or two of them at least.

I understand about unfinished projects, they all take time and some
money. I have an assortment of 488 capable test equipment, so I do have
a need for a 488 controller.


From the antenna rotator to the synthesized signal generator to the VNA
to the chart recorder and so on. And someone is on the way to bring me
some gear to repair.
I love this stuff!
Can't disagree. Finished redesigning the FPGA for a modular test
equipment monitoring design similar to a tricorder. The FPGA handles
LEDS, bidirectional I/O, neopixels, distance sensing, and serial/FIFO
for the WIFI. Still working on parts of it, but I went *very* modular
with the VHDL. Now that I have two versions (close to each other), it's
time to go back to RF networking.

Harvey


Bob
On Tuesday, October 1, 2019, 02:17:43 PM PDT, Harvey White <
madyn@...> wrote:


On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
Correct me if I am wrong, but it seems that the cables we are
discussing are little more than some wire and a couple of connectors.
Perhaps there is some electronics in there as well; I suspect so. But
isn't it maybe just level shifting?
Actually, it's a bit more than that. You have at least several
subsections. Firstly, you have I/O drivers, getting the right ones is
important for driving more loads. Next, you have the 488 chip itself.
I know of three of them that are specific controllers, and there's an
FPGA implementation out there somewhere. FPGA of the right size may be
5 to 15 dollars. Next, you need a USB to something interface, likely to
TTL serial data. You'd also (with at least the non FPGA versions, want a
processor to implement the conversion from the serial data to the
chip/FPGA. Throw in 3 to 7 dollars for that. Ask at least a dollar
fifty per PC board (and that's Chinese special, no bigger than 100mm
square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff,
and 7 for major stuff like processors, and USB interfaces. Throw in
another five dollars for miscellaneous chips, ignore the connector,and
ignore the labor to put it together, and we've got 32 dollars and then
some.

Buy in quantity, fake some chips, you're lots cheaper. Throw in
assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is
ridiculous. I can buy USB devices that can read many memory card formats
for a couple of dollars, and I suspect those aren't any simpler than a GPIB
interface cable. I can buy the nanoVNA for less than $50. So the cost of
the interface is definitely out of line.
Yes there are companies that buy things regardless of price. The
manufacturers have probably analyzed the market and have decided that it's
better to sell a few at high prices than many at lower prices. It's their
call and I am not in a position to argue. But I vote with my money and my
money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of
the market. Value is important to me, if not to the big guys who do this
stuff for a living (of which I used to be a part).
Bob
On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <
leo@...> wrote:

On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of
the
GPIB-USB-HS adapters come with a CD containing driver versions that
will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo













Re: TDS upgrades

 

On Wed, Feb 20, 2019 at 11:24 PM, EricJ wrote:


I just did a Google search myself, definitely saw some scopes that were
wearing a "TDS744" label, with no "A" in sight - so they do exist, just
unbeknownst to me prior to today... No idea what the differences are,
The TDS744 no letter had a very short life, so short it didn't even show up in any catalog.
The TDS700 family appeared first in the 1995 catalog as TDS744A and TDS784A.
The main (only?) difference from the user's point of view is that the no letter 744 does
not have the InstaVu function. As far as I know there never was a TDS784 no letter.

I scanned my TDS744 Service manual and asked Kurt to put on the Wiki and until that
happens it is here: www.hakanh.com/dl/temp/TDS684A-744_Service.pdf

/Håkan

Re: Icom IC 720A

tekscopegroup@...
 

Hi John,

This being a transceiver model with VFD display, did you check that the filament, grid and anode voltages are correct? I would think that there might be a high probability that the DC-DC converter used to generate the voltages for the display might have failed (dry caps, failed transformer, etc), before blaming the display driver itself. There is also a +5 to -5 converter associated with IC8 as it is a PMOS device that requires a negative voltage. Back in the day I repaired quite a few HF transceivers from the late 70s to early 90s, mostly from Kenwood, but some Icom units as well, although I do not recall ever specifically working on an IC-720. But I seem to remember that the DC converter was usually the weak link in some of the models with VFD displays, which where very popular during that era before the advent of mainstream LCD technology. Hope that helps, and good luck t-shooting for the problem.

Alex

Re: CORRECTION: Tom Jobe Collets have found new homes...

Chuck Harris
 

Hi All,

The remaining collets I got from Tom Jobe have all found good homes.

-Chuck Harris

Chuck Harris wrote:

One of those loose ends was to give me his remaining stock of
fan collets he made for the 2465. They were made on one of his
CNC lathes, and are simply beautiful. I told him so, but as
was typical, he ignored my praise.

I have 4 or 5 left, and if anyone needs one, I would be happy to
send one on. I would prefer that they be used for a scope that
matters to you, and not just something you want to spiff up for
a sale.

Icom IC 720A

John Stoole
 

Greetings All, I have an IC 720A that I am restoring, it is now operating TX and RX and I have also done the modification to the LPF to get rid of the "clacking" rotary
relay, and now have silent band switching. The only problem is no display, have checked the display unit in another rig and it works perfectly, have now decided the the problem is in the Logic board possibly the Display Driver (uPD549c). So I was wondering if anybody may have or know where I can get a Logic board,It would be a great pity to have to abandon this rig when it almost 100% serviceable, resprayed and looking great.
Any help would be greatly appreciated.
John
mi0dfg (N.Ireland)