I appreciate Mr. Karnes' academic approach to the solution of the problem, but my understanding is that "nickfromny" needs some simpler, real world hints to get rid of an annoying problem which is actually quite common when dealing with cables connecting buildings and devices, rather than performing investigations which are out of reach for most, both because of the skills required to use sophisticated tools like the aforementioned (oscilloscopes, reflectometers, insulation testers), but also for the cost of this gear, that can easily be higher than the cost of the whole timing installation.

Most people I know dealing with time-keeping have just some very basic knowledge of electrical wiring and have access to very simple tools like low-cost multimeters. Assuming anything beyond this may be pure dream.

First I would like to try to make some points more clear.

Buffer
Every timing device on sale has some kind of buffer.
All pulses from photocells, starting gates, etc. are recorded and 'queued' for late processing. As you may imagine, not only simultaneous pulses coming from more channels but also rapid sequences of impulses on one input channel need to be queued in a buffer (stored in memory and then processed) to accomodate the different latencies of the printer, the serial line, the display etc. and all the peripherals that may be busy or simply not ready to perform the job.
The old Alge Tdc4000 had a 18-positions buffer on the finish channel, no buffer on the start and on the intermediate channels. The start had an adjustable delay that made it impossible to record quick sequences of pulses. The intermediate channel had no buffer (i.e. too tight pulses were simply lost).
Nowadays thanks to the memory availability, all timers feature wide acquisition buffers.
ALL the devices you listed have input buffers.

Optocouplers are not buffers
Optical isolation (I'm trying to simplify as much as possible) is a means to physically interrupt the continuity of wires, preservating the logical state (typically open or short circuit). To make it more easy to understand, think about a pair of wires terminated by a simple switch. You may open or close the switch and the corresponding logical state will be OPEN or CLOSED. Now add and optocoupler. The device will carry the state of the circuit, without being physically connected (light is used to carry the information).
Different voltages may be present on the other side, but the device will only pass through the logical state of the wiring.
PLEASE be aware that one of the dangerous side effects of optocoupling is that hazardous voltages may be present between the input and output of the optocouplers.
In addition to optically coupling, some extra features may be present in these devices, like low pass filters (a pulse lasting some milliseconds may correspond to some tenth of second of output pulse. This is often known as 'delay' even if it is not a true delay, just a longer 'status-hold' on output). The device maker should be able to give you all details.
You may isolate the START wires with tools like the TAG HL-553 or the BlinkyBox,
you may isolate the serial data connection with tools like the Moxa TCC-82.

===========================

Now you need to solve your issue.
I have some suspect about the 'crazy' behavior of your START input as coming from an AC 50 Hz power leak or poor/unsafe grounding. This may also have slightly damaged your timer's inputs.
Make sure that if you use a generator, this SHOULD be grounded following the builder's safety instructions.

Let's go inside the problem. May I suggest a 'divide et impera' approach.
All you need is your timing equipment (everything, even the PC, the headsets and the score board, not just the timer), and an multimeter.
You may go el-cheapo and have one for 30 bucks. A good investment may be a professional Fluke (my favourite is the 179) or a Tektronix one. Hope admin doesn't ban me for advertising.

Unfortunately, it often happens on the hills that older power installations were unsafe, lacking proper grounding. Have an experienced technician check the electrical safety of the hut (sockets, ground, etc.) BEFORE investigating yourself.
If the hut is metal-based, ask to check that it is properly grounded.
Only then you can do some simple tests on your equipment.

Be aware of this fact: since you are dealing with cables going inside & outside the building, the category of the installation is Cat III and Cat IV. This means that in order to work on the wires, you may need special skills, training and wear appropriate protection (shoes, gloves).

Lay down your equipment. DO NOT inter-connect anything.
Just plug the power adapter to the timer, the PC and the score board.

Now check, with your multimeter:
a) The impedance (OHM) of the wires going to the start.
Open and close. Ideally should be infinite (0L) when open, and from 30 to 1000 OHM when closed. I assume the wires are longer than 1000ft;
b) Now check if there are some hidden differences of potential (voltage) between each wire and the timing hut ground (windows and walls if the hut is steel or alu built);
c) Check the voltage each wire and the electrical ground of the power sockets;
d) Check all possible voltages present between the wires going to the start and the chassis of the timer, of your PC, the shell of the serial adapter, in a word EVERYTHING which is not plastic.

Now wear the headsets, and connect them to the same cable used for the start gate.
DO NOT CONNECT the timer. Just the headsets. You should be able to talk to someone at the start without any noise.
Now connect the timer. You may hear some very light noise. If the noise is HIGH, as high to make the start unhearable, AC is passing through and thus needs to be stopped.
1) Unplug the power adapter. The noise disappears? => The adapter (which should be built with double isolation) is faulty and HAS TO BE REPLACED.
2) Connect the scoreboard. If possible check also if there is some voltage between the scoreboard's chassis and the wires going at the start.
If high noise is heard, the board may have some power leak;
3) Connect the PC's serial line (and the printer, etc.).
(Often 'switching' power supplies for the laptops and printers are a source of problems).


In one of these steps, if:
-you hear high noise in the headset,
-the start line gives you thousands of pulses,
-you find some anomalous voltage between wires and tools,
then you have identified your problem and may ask for help in a restricted domain of possible issues.

I might suggest a TDR can be purchased for $800-$1500 (just check common auction sites).

Also, just as aaron suggests contacting an electrician to perform the electrical maintenance on the building including grounding before testing the timing lines, I might suggest, as I normally do to most resorts with wiring issues I consult with, hire the local telecom expert (usually the phone company) to come and test your wire and peform the same needed maintenance. Just as you ground your electrical wire, the shield on your timing wire should be grounded at every break/junction box, connected to the same ground as your AC power, etc. Your local telecom expert will most certainly bring a TDR, charge a relatively minimal fee and they can identify issues in wire in locations, often saying you have a problem in a specific area saving you time (and possibly money). A good plan would be to have them visit every fall, test your wire and repair any problems. While your initial investment may be greater, for a small investment (certainly less than $500 a year) you can be assured your wire is ok.
Jenna

Thank you all for the education.

A question was asked.

"Happy New Year.

I was looking at a recent revision to the FIS Timing Booklet.

Here’s the clause I’m talking about:
The use of any electronic device (e.g. optocopler) between startgate and
timer or photocell and timer must be specifically compatible and authorised
by the manufacturers.

This seems to be one of those common FIS things that tries to explain
something, but is a few words short of accomplishing much of anything at
all.

I think what they are trying to say is that opto-couplers must be
authorized for use by the manufacturers of photo-cells, timers and start
gates (Tag or ALGE).

The problem is that this clause doesn’t say that. An “electronic device
between the start gate and the timer” might also mean wire, banana plugs,
bix blocks, or multi-pin computer connectors. It also says that the
electronic device “must be specifically compatible”, but it doesn’t say
what it’s supposed to be compatible with? Then it says that the device
“must … be authorized by the manufacturers”., (or the 12-year-old kids in
Taiwan who actually manufacture the electronic components that go in both
the Tag timers and the opto-isolators).

Anyway, do you happen to know if BlinkyBox brand opto-isolators are
specifically “authorized” for use?

The FIS rules are in bad need of a touch-up by someone who has a reasonably
good grasp of the English language (or at the very least a spell-check)."

A response from Ted Savage

"The original requirement for this passage about

"The use of any electronic device (e.g. optocopler) between startgate and
timer or photocell and timer"

was to defeat anyone from injecting ANYTHING "electronic" into the process
that would interfrere with the accuracy of the FIS homologated sensors or
timing systems.

Something like a reed relay or some other "electronic" device that would
add inaccuracies to the triggering or sensing of the FIS homologated
systems needed to be controlled. It has happened. We had a race in the USA
and one in ITA that featured a home-made reed-relay devices that
demontrsbly caused erratic and inconsistent trigger delays of up to 1/10th
sec. We only found out about it AFTER the race was scored and there was
nothing that specificaly prevented their use.

Additionally, for as far back as I've been doing World Cup (1984) all
professional contractors used these isolation devices and since 1995 when
the Timing Rules went into force and I bet few of them had ever been
checked for compliance to basic accuracy (other than the ones we built and
used).

This passage AND the requirement for a separate "FIS" timer that monitors
the 4 A/B start and finish channels at World Cup are linked thinking.
You've got to be able to technically and forensically prove that the
triggering, sensing, and timing are not being affected in the chain of
devices. Try explaining THAT to the IOC.

The text of this requirement puts the onus on the "manufacturers" of the
timing equipment to specifically authorize optocoupler choices and
compatibility of such a component. It's interesting that someone would pick
up on the fact that it's confusing as to which "manufacturer" is
responsible for this. It says "manufacturers", thus "all" involved are
equally responsible to assure intercompatibility. I guess I need to stop
hanging around with Lawyers. In fact - I'm sure of it.

The use of any 12-year-olds aside, I can confirm that the optocouplers
mentioned below are compatible with all FIS homologated timing and sensor
devices made by TAG Heuer and ALGE. Between Jean Campiche (TAG Heuer),
Albert Vetter (ALGE), Timing Guys (Jim Karnes) and myself as the
authorizred intermediary who has to use them in varrying combinations at
World Cup - we attest to their interoperability as required by the FIS.

- TAG Heuer HL553 series
- ALGE OC Series
- TimingGuys (Blinky Box) series

We have used all of these products in World Cup for quite some time. I have
personally checked their accuracy against parallel-redundant technology
both in our labs and in high level events. We (Precision) participated in
the design of the original TAG Heuer 553 series and now the Timing Guys
Blinky Box optocouplers to expand on the number of available channels
needed for events like Kitzbuhel (where I need 24 discreet channels to deal
with all of the deployed sensors ), and added a selectable "link" option.
They are all interchangeable with devices from these "manufacturers" (TAG
and ALGE).

This authorization has been communicated to the FIS where I have tabled
these results in the FIS Timing Working Group as each device has come up
for compatibility testing by us since 2004. I have done this for the
manufacturers listed here because we have been best placed to do so. I
suggested to the TWG they be specifically included on the timing equipment
homologation document to remove any doubt - but there are issues with
"manufacturers" other than TAG and ALGE and how they would accept such
testing and authorization. That's their problem - not mine. I guess the
answer in those cases is "no" until they specifically say so.

All of this technical detail and supplemental discussion was covered in our
FIS TD Update sessions starting in 2004 when this optocoupler requirement
was originally issued. All clarifications on this topic (and about 400
other topics) were distributed to all national associations of the FIS for
official's training. I guess it's a question of how each nation gets the
word out. Some FIS nations require timing operators to be specifically
trained and qualified - but Canada does not. That too is something that
the NOC in CAN is specifically looking at and that we hope to solve over
time. Everyone in FIS needs to know what the Updates cover. That;s why I
post everything we DO cover on nafistd.com

The concept of an "electronic device" does not include "wire, banana plugs,
bix blocks, or multi-pin computer connectors". The specific example
reference to "(e.g. optocopler") takes care of that device distinction.
Connectors and wire do not qualify as an "electronic device" in the sense
that we defined them here and cannot inject inconmsistent delays into the
signal chain to the magnitudes we test to.

The commentary about the FIS Rules text pronlems are valid, but as a
volunteer they are frustrating. Dave Pym, the volunteer member from CAN of
the 26-member-stroing FIS Rules Committee is doing the best he can. Dave
and about three others strive to add clarity to the difficult task of rules
tracking and revision in the 4 official FIS languages for everything
published by FIS. Everything. It is not a simple task, often a thankless
one, and many helpful revisions have in fact been rejected by other FIS
committees. Yes, there is much work to do. One tries. It's complex. I
assure you that Dave has "spell-check" and he has a "good grasp" of
English, even if he is from BC and uses works yet to be invented from
time-to-time. I'm from Québec - so don't talk to me about language issues.
All suggestions for changes to FIS rules are welcome and appreciated. Just
remember that ALL of this is volunteer work. If there are any specific
suggestions please feel free to submit them (actual text) and I'll make
sure my colleagues in FIS see them and consider them.

Anyone using any other FIS homologated sensors or timers will have to check
with the timing device "manufacturer" to see if what they are using as an
optocoupler is in fact compatible with those systems
(Longinnes/Omega/MicroGate/Summit for example). I have no idea as to their
compatibility and there has been no technical statement tabled from these
manufacturers to FIS as far as I know.

Some clients have checked with me when these purchases are made from all
over the world just to make sure and it's nice to see someone paying close
attention like this. It's a good and valid question.

The next FIS meeting is in Dubrovnik CRO in the spring and I will table
this specific discussion to my volunteer colleagues on the TWG, FIS Rules
and the TD Commission to attempt to clarify this important element. Thanks
for highlighting what is considered to be problematic and we'll all try to
do better.

Hey, at least it's not a bad as swimming or luge.

Sincerely and with best regards

Ted"

There still seems to be some confusion about the proper use of optoisolators for finish lines of sanctioned Alpine ski races.

Blinky Box by Timing Guys Inc = Only use with the "link" switch turned off

Tag Heuer 553 = Use channel 1 for primary cell input and output. Use channel 2 for backup cell input and output. Do not jump inputs together with banana plug jumper.

Tag Heuer 553/ FIS DO NOT USE for finish line! This is an either/or device that will take either input and then distribute the pulse to ALL connected timers. This unit was made to be used for intermediate points and unfortunately
is not labeled correctly.

ALGE OC-18 or TIDO-OC = use normally for all instances.

Microgate REI2 = Has selectable optocoupling built in. Do not use with the Blinky Box or Tag 553 as it is not needed.

Finally had issue Snobro had. TAG Opto coupler failed and was getting many false starts on my 540. One side of Opto coupler was dead, set it back for repair. False start issue happened when using FIS Alge Start Gate. Open gate still sends out a short that this TAG 540 picked up. Blocked input for 15 seconds to fix and allow starter to return the gate to its closed position. My other 540's aparently are not as sensitive and do not do the same thing.

FRom GT at Reliable."That TAG 540 had firmware version B09 in it. Upgraded it to the current version B11. Works fine." I am checking my other 540's and upgrading firmware.
N.