Datatran Auto Fox AF-120 .... anyone familiar with this monitoring unit please ? - Page 1
Forum section: electronics / testgear

author: Fraser
author_rank: Super Contributor
timestamp: March 30, 2018, 02:12:13 pm
content: I recently purchased a Datatran Auto Fox AF-120 and breakout boxes that dates back to the 1980's. It is a RS232 and Parallel port monitoring device but sadly my unit looks to be minus its user manual.Datatran are now long extinct and I have found out very little about the unit beyond its basic purpose. I work with RS232 a lot so these units do have a use for me. I know people think RS232 is old and obsolete, but I work on very expensive kit that still uses this resilient communications method. Often a laptop is used with suitable software for RS232 work but I like the idea of a nice compact unit that was designed for RS232 diagnostics. I also purchased another unit, a Trend 110, but will ask about that in another post.Has anyone used one of these Auto Fox units please ? If so so, I would love to hear about its functionality and usefulness. Mine is shipping from the USA so will take a week or two to arrive.Many ThanksFraser

author: postfive
author_rank: Contributor
timestamp: August 20, 2020, 07:45:34 pm
content: Fraser - here in 2020 this is coming to you over two years later but hopefully this will help you and others. When searching for information on Datatran AutoFox on the web, this EEVblog post comes up as one of the first ones. Additionally, you still see these units available on eBay, so it is likely that others will head over here for some info.I worked from 1987 to 1997 for a minicomputer VAR and was in charge of the field service department; our customers had many different types of serial and parallel printers as well as serial input terminals (think VT-100/220 compatible). Many of the printers were high-speed line printers that had extended line length capability up to 200 characters. We needed some test gear to exercise them and fairly early on when the AF-110 became available on the market I purchased one for the shop. I don't remember exactly what the difference was between the AF-110 and your AF-120 but it was fairly minor; probably more buffer RAM inside; it might also have been that the 120 was packed with a few more accessories. Both units have the same basic functionality. Perhaps you or someone else can post the menu structure or differences that exist from their AF-120 and menu structure I have documented below for the AF-110 here.I liked the unit a lot and used it a ton; I had configured my own special barber pole test that used a 200 character line length into the buffer to fully test our line printers. Note that I purchased ours fairly on when they first were introduced; the later versions had more capabilities than the early versions which I don't believe included barber pole in that mode. I never got one of my own at the time and always wanted one, but I just recently acquired one on eBay. Alas, that did not come with a manual either and 25 years later the memory fades, but no worries; one nice thing about the AutoFox product was its extensive help menu. The interface is really very intuitive and even if you don't have a reference sheet, it is very easy to figure out.I've included here a write-up that I did for my own unit which has a date code of 1995 (and spiffed it up some for this blog), so it is for a later version than the one I had at my shop. Datatran added new features to the product over time; if you have an earlier version yours may vary slightly from the menu descriptions below, and some of the display text prompts may be different.Datatran AF-110 AutoFox Serial/Parallel Data Generator / Tester / AnalyzerThis is a very comprehensive and nicely engineered compact hand-held test instrument that came out on the market in the 1990's.It was designed to generate, store, or analyze data streams to or from Serial RS-232 or Parallel (Centronics standard)interfaces. It has the capability of generating bit/data patterns pre-stored in the device (Quick Brown Fox or barber pole), oryour own custom configuration. The Serial and Parallel interfaces are completely configurable where appropriate for the data bytesize, data pattern, ASCII or Hex/Octal character set, speed, flow control, line size, line termination characters, device sensesignals, and block line or file mode with end of file character configurable. Data can be sent in single-step, continuous mode,or continuous-till-error-detected mode. Serial data speed can be sent in preset or in "autobaud" mode; Parallel data can be sent aline at a time or continuously.The unit has a DC barrel jack connector on the top left for attachment to an AC adapter, and a slide-type power switch on the topright. The LCD display consists of two lines of 16 segments each. A 9-pin Serial connector is on the left side, and a 25-pinfemale connector for Parallel devices is on the right side. Note that a special converter must be used on this connector to allowit to be attached to industry-standard Centronics interfaces; the choice of a 25-pin connector being used here was to make theunit as compact as possible. A four-button user interface panel is on the bottom; Exit/Stop, Enter/Start, and two Change Scrollbuttons, allowing left or right scrolling.One of the main features that makes this unit so powerful is its storage and programming capability. It contains a buffer memoryspace which is user configurable; this space can be held as one Main space, or split into multiple sub-buffers each with their ownuser-defined alpha-character name for identification; this allows the user to load their own customized test patterns into the unitif the built-in Fox or Barber pole test patterns are not sufficient, or to capture external data in one or more independent memoryspaces. Data patterns within the built-in ROM memory or the user buffers can then be sent out the serial or parallel ports to testdevices. The unit can also receive data from the serial port; this can be stored and then subsequently sent out the unit fordownloading to another device or for testing. Thus this unit can be used as a data capture device in the field for small amounts ofserial data (within the limits of the total buffer space and/or the specific sub-buffer you may be interacting with) or for customizedbit pattern tests. Available buffer memory varies depending on how the device is configured but in general there is slightly over20,000 bytes of space available for data storage or customized test patterns.The BERT function (Bit Error Rate Test) function allows you to analyze a Serial device connected to it to determine whether it isfunctioning properly. Receive bit and block errors, sync loss, and frame errors can all be detected and summarized.Note that in the following description I refer to 9-pin serial connectors using their proper designation, i.e. DE-9S for a 9-pinsocket, or DE-9P for a 9-pin plug, rather than the common misconception where they are referred to as the DB-9 series. Thishas always been a major gripe of mine; nobody seems to use the proper designation. This is so confusing that even Datatranthemselves refer incorrectly on the back of their own adapters to the 9-pin series as DB rather than properly calling them DE!To explain this further, several industry-standard D-style connectors exist with differing widths to accommodate the number ofconnector pins; these widths are differentiated with an alpha character following the D depending on the particular connectorbeing used. The DB designation is for 25 pin D-style connectors while the DE designation is for the narrower 9-pin connectors.A built-in comprehensive help menu paired with a very intuitive user interface means that even without a manual you can use thisdevice to its full original potential even decades later without too much of a learning curve. Unfortunately, Datatran went out ofbusiness decades ago; however this instrument is still very viable today for maintenance and support of legacy serial and paralleldevices including but not limited to serial and parallel printers, serial display terminals, serial data loggers etc. They pop upon eBay every so often; prices vary from around $50 to $300 or more. To the best of my knowledge the unit was originally soldwith the following accessories:1 vinyl two-pouch case with attached carrying strapThe user / operations manual1 long (approximately 6') 25-pin ribbon cable with DB-25P plugs on each end1 short (approximately 1') ribbon cable with a DE-9S female socket on each end1 special adapter with a DB-25S female to male Centronics Parallel1 Datatran AutoFox Serial Adapter with TX and RX LEDs, a DB-25P to DE-9S on "Printer" end, and a DB-25S to DE-9Son the "PC/AT" end. On the rear side, the pinouts are shown for the AutoFox DE-9S socket, the IBM PC AT DE-9Ssocket, the IBM PC/XT DB-25S socket, and the printer DB-25P plug.1 "wall wart" AC power supply to convert 120VAC (US power) to 7.5 VDC, rated at 100 MMost of the accessories can be replaced if they are missing; clearly if an item for sale has most/all of the above accessoriesthen the price can go higher. One might think that the most critical item is the user/operations manual. That's the oneoriginal accessory that cannot easily be replaced (as of this date there does not appear to be one available anywhere on theweb - perhaps someone with an original can help out!); but because the built-in help functions mean that even without it youcan figure out how to use it, you really don't need the manual. Probably the most critical item is the adapter needed to connectto Parallel devices. This along with all other accessories can be replaced by your own substitute items, but due to the specializednature of the conversion between the 25-pin DB style Parallel output connector to the 36-pin Centronics industry standard Parallelconnector the internal wiring is not obvious (I will provide a pin conversion chart soon). If you are in Europe, you should beable to find an appropriate wall wart style to match your wall plug configuration and modify its output cord to fit the properbarrel jack connector on the other end to attach to the tester. I don't know if Datatrtan ever came out with a 230 volt version;it would certainly have provided them with a much broader market if they had.You will probably find that a few additional accessories will need to be added to the basic kit. These include FF 9 and 25 pingender changers and possibly a longer 9-pin cable with appropriate ends to meet your needs. Additionally, the DatatranDataTracker full RS-232 breakout box is often paired with the AutoFox to provide much more functionality. The DataTracker breaksout all 25 pins on both sides of the connection, with separate LEDs for each pin indicating high/low signal status and a breakoutpin for each signal, along with isolation DIP switches for each pin. This unit normally came with some attachment cables andsome spring-loaded clip patch cables to allow a quick custom field configuration.There are 4 internal Ni-CD cells soldered to the PC board; since the device is now several decades old it is possible that thesemay need to be replaced, and some corrosion or leakage may need to be removed / cleaned up. Internal batteries mean that the unitis completely portable. The AC adapter will be mainly needed to recharge the batteries or when testing a device over severalhours or days.At power-on, the unit displays:DatatranAutoFox AF-110Press any key to access "Configure" section. Press "< (Change Scroll)" key to access "Tool Kit" section.If any one of the buttons are depressed while turning on the power, the unit goes into "Configure" section on button release.If "Exit" and "Enter" are both pressed and then power is turned on and then they are immediately released, the display shows the"Configure" section.If "Exit" and "Enter" are both pressed down while power is turned on and they are held down OR if both are depressed at oncefrom the main menu, the display shows:"Button Help""General"If "Exit" and ">" are both pressed and then power is turned on, the display shows:System ClearSettings? No("<" or ">" select Yes or No, press Enter to take desired action)It then displays:System ClearBuffers? No("<" or ">" select Yes or No, press Enter to take desired action)The display then shows the normal power-on message.If "Exit" and "<" are both pressed down while power is turned on (can be held on or not) the display shows the Serial number,Revision number and manufacturing date. Example:SN: 110872 1A-1BKJ 01-18-1995All other button press combinations not defined above when powered on will cause the unit to display the power-on message."Button Help" menu:General (below refers to the 4 keys; X = Exit/Stop, N = Enter / Start, U = upper >, D = lower <)X Exit Cur LevelN Enter/AcceptU Change Opt/ValD Change Opt/ValTransfer DataN Resume OutputN Pause DisplayU Turn Flow OnD Turn Flow OffEdit DataN Change ViewU Scroll RightD Scroll LeftNU Search RightND Search LeftXU Change CharXD Change CharXNU Insert SpaceXND Delete CharChange/CreateNU Inc by 100ND Dec by 100View Start/StopN Change ViewU Scroll RightD Scroll LeftNU Search RightND Search LeftXU Goto StopXD Goto StartXNU Set StopXND Set StartPower OnXU Sytem ClearXD Display Info (SN#, Version #, Checked by technician initials, Manufacturing Date)UD Make Test BufKeep in mind that for the following menu patterns, the exact options and configuration settings may be different on your unitdepending on the firmware version. I have tried to accurately capture the configuration setting options from my own unit;yours may vary. Any formatting or indenting issues (especially tabulation) here are facets of the web interface and arebeyond my control, but I can send my original document via email to anyone who wants it if this gets totally hashed. I amusing three dots in a row (...) below to indicate identical behavior for additional buffers if they exist. Finally, any spellingerrors or other issues are entirely my own and not those of the manufacturer. This is what I have on my unit:Configure MenuSerial Port (press Enter to cycle through below options, < / > to change sub options)Baud Rate50 / 75 / 110 / 150 / 300 / 600 / 1200 / 2400 / 4800 / 9600 / 19.2K / 38.4KParityNone / Even / OddData Bits7 / 8Stop Bits1 / 2FlowNone / All / DTR/DSR / CTS/RTS / Xon/Xoff / User DefinedParallel PortModeActive / PassiveAcknowledgeOn / OffBusyOn / OffPaper EndOn / OffSelectOn / OffErrorOn / OffInitializeOn / OffLine ParametersLine Size080 (default, user configurable with < / > buttons)Line TerminatorCR - LF / CR - Only / LF - Only / None / User DefinedEnd of FileNone / Form Feed / Control Z / User DefinedBarber PoleBegin Barber (user configurable, example follows):20 032US 1F 031RS 1E 030GS 1D 029etcEnd Barber (user configurable, example follows):(space) 7E 126} 7D 125| 7C 124{ 7B 123etcCharacter SetASCII / Hex/OctalCustomizePower-up MessagePower-Up Line 1 (whatever user inputs)Power-Up Line 2 (whatever user inputs)Power-up Message EnableNo / YesQuikSetAdd SettingDelete SettingContrastHigh / Medium / Low / LowestTool KitFox Mode<----------------SerialFox PatternBarber PoleRun ContinuousExit Start Fd BdSingle StepExit Line Fd BdQuick Brown FoxRun ContinuousExit Start Fd BdSingle StepExit Line Fd BdMain (buf) (if configured by user)Run ContinuousExit Start Fd BdSingle StepExit Line Fd BdTest Buf (if configured by user)Run ContinuousExit Start Fd BdSingle StepExit Line Fd Bd...Parallel ------------->Fox PatternBarber PoleRun ContinuousExit Start Fd BdSingle StepExit Line Fd BdQuick Brown FoxRun ContinuousExit Start Fd BdSingle StepExit Line Fd BdMain (buf) (if configured by user)Run ContinuousExit Start Fd BdSingle StepExit Line Fd BdTest Buf (if configured by user)Run ContinuousExit Start Fd BdSingle StepExit Line Fd Bd...Data ModeTransfer DataFrom <----------------SerialTo Parallel-------------->Awaiting DataTo Main (if configured by user)Awaiting DataNote if buffer has data in it already, then:ReplaceAwaiting DataAppendBuffer FullNote if another buffer has been set up, then:To Test BufReplaceAwaiting DataAppendBuffer Full...From Parallel-------------->To <----------------SerialAwaiting DataTo Main (if configured by user)Awaiting DataNote if buffer has data in it already, then:ReplaceAwaiting DataAppendBuffer FullNote if another buffer has been set up, then:To Test BufReplaceAwaiting DataAppendBuffer FullFrom Main (if configured by user)Awaiting DataNote if another buffer has been set up, then:From Test bufTo <----------------SerialAwaiting DataTo Parallel---------------->Awaiting DataTo MainTo (multiple user-defined buffer names IF THEY ARE DEFINED)From <----------------SerialAwaiting DataTo Parallel---------------->Awaiting Data...Edit DataMain<New>(multiple user-defined buffer names IF THEY ARE DEFINED)Search String0D 0A XX XX (User configurable)Monitor DataFrom <----------------SerialTo MainAwaiting Data(To multiple user-defined buffer names IF THEY ARE DEFINED)From Parallel-------------->To MainAwaiting Data(To multiple user-defned buffer names IF THEY ARE DEFINED)Hex Dump<----------------SerialMain(multiple user-defined buffer names IF THEY ARE DEFINED)Parallel---------------->Main(multiple user-defined buffer names IF THEY ARE DEFINED)Buffer Mode (Available buffer space can be one single space called Main, or Main plus user-defined spaces. Totalspace available is somewhere over 20,000 bytes (varies with configuration)Change / CreateMain<new> (multiple user-defined buffers)Enter Name:Space Left (decreases with additional user input)Note - if a user-defined buffer already has been created and selected, its size can be configured hereby pressing the < or > buttons to decrease or increase the available memory in that buffer. Thedefault size is 100 bytes shown on the bottom line, with total available memory space leftdisplayed on the top line.View Start/StopMainShows buffer data pattern. If no data exists in the buffer, then NU appears for each characterrepresenting a null value.(multiple user-defined buffers IF THEY ARE DEFINED)Shows buffer data pattern as above.Protect Buffer (buffer to protect is selectable by pressing the < or > buttons)MainP (selectable by pressing the Enter/Start button.(multiple user-defined buffers IF THEY ARE DEFINED)P (selectable by pressing the Enter/Start button.Clear DataMainShows P if Protected, must unprotect first to clear MainClear All / Clear from ST-SP / Save ST-SP(multiple user-defined buffers IF THEY ARE DEFINED)Shows P if Protected, must unprotect first to clear named bufferClear All / Clear from ST-SP / Save ST-SP...Delete Buffer (buffer to select is chosen by pressing the < or > buttons)(name of buffer IF DEFINED)Shows P for named buffer if Protected, must unprotect first(buffer memory can define Main or a combination of Main plus user-defined buffers)Delete?No / Yes...Edit Data (if user-defined buffers containing data EXISTS):Main(New) if Main buffer exists but is emptyAdditionally named buffer (if user DEFINED)...AutobaudAutomaticReady to Recv.Single CharSend me an "A"Printer BaudAutomatic (may need to power-off if it hangs here)Cycles through baud rate. parity, number of bits, number of start/stop bits on first lineExit StartSingle Test (allows you to configure baud rate, parity, number of bits, number of start/stop bits with U/D)Shows baud rate, parity, number of bits, number of start/stop bits on first lineExit TestYes / NoSpeed TestThruput Speed<----------------SerialThruput:0 CPS (for unattached device, varies when attached).Parallel-------------->Thruput:0 CPS (for unattached device, varies when attached).Printer Speed<----------------SerialPrinter PatternBarber PoleExit / Start(shows DSR / CTS status on first line)Quick Brown FoxExit / Start(shows DSR / CTS status on first line)Main (whatever user has in the buffer)(will show DSR / CTS status on first line IF EXISTS)(optional user-defined buffers IF CONFIGURED)(will show DSR / CTS status on first line IF EXISTS)...Parallel-------------->Printer PatternBarber PoleExit / Start(Shows NOT SELECTED on first line if no printer)Quick Brown FoxExit / Start(Shows NOT SELECTED on first line if no printer)Main (whatever user has in the buffer)(Shows NOT SELECTED on first line if no printer)(optional user-defined buffers IF CONFIGURED)(Shows NOT SELECTED on first line if no printer)...BERT (Bit Error Rate Test)SetupBERT Pattern63 / 511 / 2047 / Alt. 01 / Mark / Space / Quick Brown Fox / Main / (user defined IF AVAILABLE)BERT Block Size (Line 1)2 / 4 / 8 / 16/ 32 / 64 / 128 / 256 / 512 / 1024 / 2048 / 4096 / 8192 / 16384 / 32768Test Length / 8 / 16/ 32 / 64 / 128 / 256 / 512 / 1024 / 2048 / 4096 / 8192 / 16384 / 32768 /Test Continuous / Test Till Error(gets longer, shown in Minutes and Seconds, with above increasing block sizes)Run TestExit Error (displayed if no device attached)ReportingDisplayTotal Bits Sent: (first line)second line = numberTotal Blks Sent: (first line)second line = numberInjected Errors: (first line)second line = numberRecv Bit Errors: (first line)second line = numberTotal Bits Recv: (first line)second line = numberBit Error Rate: (first line)second line = number %Recv Blk Errors: (first line)second line = numberTotal Blks Recv: (first line)second line = numberBlk Error Rate: (first line)second line = number %Sync Loss Count: (first line)second line = numberTotal Run Time: (first line)second line = HH:MM:SSPar./Frame Errors: (first line)second line = number<----------------Serial(doesn't display anything if Serial not connected, otherwise same options available as above)Parallel-------------->(says Not Selected if no device is attached)

author: Fraser
author_rank: Super Contributor
timestamp: August 20, 2020, 10:47:54 pm
content: Postfive,Welcome to the forum and thank you for taking the time to provide so much detail on the Autofox unit.I still have my unit and it appears that it cane with all of its accessories and it is in lovely condition. As you say, it needs a new battery pack so I must get around to fitting one. My unit has not been used since I got it due to other commitments but I will now take a good look at it as it appears very useful. I bought a Trend 110 at the same time and that is a true beast of an RS232 analyzer ! Thankfully that complex unit came with a full set of accessories and user manuals ! I bought an amazing Agilent Adviser J2300E laptop based data analyzer last year as it was brand new and with masses of accessories. That is my main RS232 analyzer but the portable nature of the Autofox makes it still a very useful unit.Thank you again for this useful information. I will compare your menu system with the one on my unit.Fraser

author: Kean
author_rank: Unknown
timestamp: August 21, 2020, 05:43:47 am
content: I also have a Trend 110 on the shelf which hasn't been touched in some time. Thanks for the reminder.

author: postfive
author_rank: Contributor
timestamp: August 21, 2020, 07:02:48 pm
content: My unit has a date code of 1995 but surprisingly the 4 internal cells look in great shape; no fuzz or crud. When I got the unit and turned it on, not surprisingly nothing displayed but after about 5 seconds after that the display lit up. Pulling the charge cable out, it stayed on for about a minute, indicating that they were taking charge. So I left it on the charger for 24 hours, then ran a continuous fox text at 34k baud to stress it a bit; it stayed running for 9-1/2 hours! I find it hard to believe that original cells 25 years old would still be that good, but then again NiCd technology has totally different charge/discharge characteristics and the internal chemistry is different from other types, such as non-rechargeable alkaline cells which are notorious for leaking. So I have to wonder if my unit really has original batteries installed or perhaps sometime in its life they were replaced. I looked for date codes on each one but did not find any on the visible portions. I may open the unit up again and cut one of the leads to each individual cell one at a time, then measure the voltage and current drain just for fun.

author: Kean
author_rank: Unknown
timestamp: August 26, 2020, 07:38:57 am
content: I pulled my Trend unit out of storage, and it turns out it is the DataTester 105 (not the 110). I don't think I've used it in near 20 years. Not surprisingly it wouldn't turn on or charge.Opening it up the battery pack (7 x NiCd C size?) were somewhat fuzzy. The battery connector and one of the fuse holders were extremely corroded. I replaced those, and it now powers on, shows text on the LCD, and responds to buttons. I don't think the battery is likely to take a charge, but I'll give it a few hours to see what happens.Interesting construction inside. Four separate PCBs layered on one another and interconnected in a left/right zig-zag. I didn't pay too much notice, but saw a Z80 CPU and some EPROMs.

author: postfive
author_rank: Contributor
timestamp: August 26, 2020, 03:09:06 pm
content: Ya that's funny you mentioned this; I searched on the web for Trend 110 and couldn't find any reference; so this explains that puzzler. I have since supplemented my unit with all the original adapters it would have come with and more; sex changers for both 9 and 25 pin serial, and a 25-pin MM ribbon cable and two 9-pin ribbon cables. The trick there is to outfit it with everything you would ever need in the field, yet have it all fit comfortably in the zip-case. Have yet to trace out the wiring diagram for the 25-pin to 36-pin Centronics adapter but will do so for this thread even if you don't need that as others may.

author: Kean
author_rank: Unknown
timestamp: August 26, 2020, 04:02:16 pm
content: Fraser shows a pic of his Trend 110 in this posthttps://www.eevblog.com/forum/testgear/trend-datatester-110-anyone-know-about-this-data-tester-please/It actually looks like it would have been a really useful device in its day.

author: Fraser
author_rank: Super Contributor
timestamp: August 26, 2020, 07:55:59 pm
content: I own a Trend 105 as wellI will have to look for the 108 model some timeThe Trend 110 appears to have been a data tester “on steroids” and my unit came with a preliminary and final set of manuals so it is an early release. I have no idea how many of the Trend 110 units were produced but I have not seen another before or since my purchase. The Trend 110 has optional modules for different data systems So theoretically could be updated to newer communications standards as they were developed. An interesting bit of kitFraser

author: postfive
author_rank: Contributor
timestamp: August 26, 2020, 08:53:18 pm
content: Nice, thanks! Does the Trend have pre-configured bit patterns such as Fox or barberpole? I assume that one advantage of it over the AutoFox would be easier input of customized data patterns due to the built-in keyboard. Did it have the capability of storing external data? It looks on appearance to have come out in the 80's; correct me if I'm wrong. At that time, it was probably a very trend-setting device (no pun intended).The AutoFox came out in the 90's, and has these main features: 1) It is very portable. 2) It is totally configurable for bit and data patterns. 3) It has data buffer capability built-in so you can capture data in the field for analysis back at the office or for collaboration with factory service. 4) Built-in BERT. 5) relatively inexpensive compared to competing test gear. 5) It can test Parallel devices as well (I used that feature probably more than the Serial side due to the requirements of my customers and the types of peripherals they had).As an old field service guy who had to lug a Tek 465B scope and a 60-lb toolbox plus repair parts through metro downtown streets with inadequate parking facilities and then get up to the 23rd floor of an office building to the client site, portability was one of my main considerations. The AutoFox won out over any other products from that perspective, and it did everything I needed it to. If I needed a custom pattern I could create it there at the client site either manually with the keypad or downloaded from an external computer. Better yet, pre-configure a specific custom pattern at the office, load it into the AutoFox, then take it to the field.Data patterns from errant devices in the field could be sent off for analysis. I remember we were called in to fix a really gnarly optical character/bar-code reader problem that affected a retail chain store with multiple locations. The equipment had checked out initially at the factory and at the initial install at the customer site but then started failing several weeks later, producing gibberish on scans. The customer was screaming; productivity down at multiple stores, so high pressure. Electrically everything checked out, so I knew it had to be a data problem. I used the AutoFox to capture the data patterns from a brand-new reader and from a failing unit against a factory-standard bar code test pattern and sent them back to the factory for analysis right from the client site, which impressed the customer (yep, their IT guy was watching my every move and staring down the back of my neck the whole time!). It turned out to be caused by a bad batch of EPROMS which started failing only after they had been installed in the field for several weeks due to the use of inadequate light-blocking material on the chip windows (if I remember correctly these were early 2708 EPROMS) and they were slowly dropping bits. Light was able to get into the units through an unused cord access hole that the EPROM was facing (poor engineering design IMHO). We were able to replace the chips (socketed!) and block the unused cord access hole - result, happy customers.Maybe we should start a new thread that talks about the strange things that can happen in field service from an engineering perspective! I've got a good one involving a tractor repair shop and a multi-platter hard disk if anyone is interested! Another one - Jameco Electronics recently posted one I sent in that talked about an early computer company I worked for where the disk controller board had its printed circuits laid out 180 degrees out of phase on the buss. An yet another incident involving mice, an 8" floppy drive, and a salad dressing bottling line. Oh, the memories!