Mark,
1) First off, please accept my sincere apologies for misunderstanding what you wrote earlier!
When I read your fervent post, stating your adamant disagreement with Bill's seaman-like recommendation, I understood you to be making a blanket recommendation "for" the use of a "splitter".
But, now I see that you actually do agree with me, that every individual sailor should understand exactly what they are dealing with, and how these devices may effect things, and that they should be given the facts / knowledge in order to make decisions (as you and I have done).
{In my own defense of my misunderstanding, remember that at that time, none of us knew what the original poster's precise need was, nor exactly what his
current VHF system consisted of, state of the cable/connectors, etc....nor even more importantly whether he understood the technical specifications, nor how they may effect his system, nor whether he understood the various possible issues a "failure" could cause, etc.....so...
So, I misunderstood you, in that I that I assumed that you were making a blanket recommendation "for" using a splitter...sorry about that!!}
Quote:
Originally Posted by colemj
Nobody here has made a blanket recommendation "for" splitters. If you are implying that I have, you did not read my very first response to the OP, nor did you read a subsequent post where I specifically made this clear.
Bill did make a blanket summary recommendation "against" splitters. Is he a bad engineer and a bad seaman? |
It appears that you were taking issue with Bill's
posting, where you interpreted him to be making a blanket recommendation "against" splitters.
Where as, I interpreted Bill to be giving seaman-like
advice to an unknown sailor on the
internet, that there are too many variables / technical details for the average sailor to understand, and therefore because of this, he was advising this unknown sailor to install a second VHF antenna (on the stern rail,
bimini top, arch, etc,), and use this as his AIS transponder antenna.
Which is why I wrote: "in general I agree with Bill here....
for most cruisers, his advice/recommendations are good..."
So, again, please accept my apologies for the misunderstanding.....that's one of the problems discussing tech stuff on-line....but, no worries!!
2) Secondly, the above notwithstanding, I would like to politely take issue with you calling me a liar and then further insulting me by calling me lazy...
Quote:
Originally Posted by colemj
The failure modes you list later are just general failure modes of electronics - radios in particular - and many of them have to do with components that are not even part of a splitter (a preamp?).
All but one of them results in ensuring the VHF still operates, so the continued fear about putting ones VHF safety in jeopardy is strange. The other one is a nebulous "preamp oscillation" that leaves both radios open. That one is pretty much a fantasy - it will have nothing to do with a splitter failure, and has never been recorded EVER in a splitter.
And almost all of them rely on a lightning strike so surgically precise that it does not take out any other components, while going unnoticed by the user.
You and Bill can ignore responding to me all you like, but since you two have considerable expertise in these things and are looked upon for advice, I will hold your feet to the fire when you are lazy or relying on unexamined beliefs or out-dated technology. Which both of you are doing in this example.
Mark |
Mark, I do not know you and you do not know me, and in polite society this kind of unprovoked and unsubstantiated attack is quite rude and in all honesty disturbing to me....(if I knew you personally, I'd have given you a call and asked if you were okay, and was there anything I could do to help...perhaps take you out to lunch...we got good BBQ down here!
Since I do not know you, I'm left wondering what to do....
And, here is what I decided...
I'll just post a few personal facts from my life, politely ask you to believe / understand that this IS the truth...and hopefully you'll simply accept this as fact and apologize to me for calling me a liar and lazy...
a) I wrote earlier that I do not know of any SP-160 failures, and I have had nomissues withn my SP-160....but I have personally experienced "splitter" failures, pre-amp failures, relay failures, etc....and most have NOT been caused by
lightning strikes, certainly not by direct strikes...
b) You write that splitters and relays do not fail, and especially when you write that pre-amps do not fail, EVER, when I just got done writing that I HAVE had them ALL fail in multiple ways, yes, even pre-amps oscillating (causing blocking of the receivers connected to them)....
[BTW, the Vesper SP-160 does have a pre-amp in it....as does the other "zero-loss" splitter....oh, and please understand that what everyone here is calling a "splitter" is in fact a "relay/splitter" combination, and the SP-160 (and the other "AIS splitters" that have pre-amps in them) is a "relay/splitter/pre-amp" combination....
Do you really think I was
posting about things that are not true??? (ah, yes you did....because you called me a liar...)
Seriously, sir, it seems you are not as informed as you thought...]
So, if you care to read this truth, in more than 30 years in
communications (some of these failures just this past couple years, with modern 21st Century devices, not "ancient history"):
--- I HAVE personally had 2-way transmit and receive relays and splitters fail, in multiple ways....VHF/UHF cross-band couplers (2-way freq-dependent transmit and receive splitters) fail....in-band receiver multi-couplers (2-way, 4-way, and 8-way, receive splitters) fail....all from either close lightning strikes, or from direct lightning strikes....
Some of these are on my own personal tower at home, some are on my broadcast tower, some have been on others' towers...
{please take note, in the many 100's of direct strikes my
equipment has experienced every year, for many years now....I have had VERY FEW actual failures!!! The broadcast tower (1368' high) where I have some of my own
equipment, is struck many 100's of times each year (i should write 1000's of times, but some years it's been only a bit over a 1000....so, I'm being conservative here...)}
--- I have also had T/R relay or RF-sense relay failures....sometimes just burnt contacts from lightning arc-overs, but sometimes just a failure over all...
--- Also, as for "pre-amp" failure....well to say that it happens often would be an overstatement of course (and I never wrote that it happens often)....but it does happen...
Since I end up fixing some of the pricey ones myself, I am very familiar with these....here is a a list off the top of my
head....
I have personally had receive pre-amps fail....you may be surprised to learn that the "total dead" failures were usually the result of close lightning strikes, not direct strikes....(btw the broadcast tower has a "counter" that trips for each direct strike, so I have some pretty hard facts here!).....
I have also personally seen others with similar
commercial and amateur VHF and UHF pre-amp failures....
Also, I have personally had both a D432 vhf pre-amp and a MGF1312 vhf pre-amp, oscillate, and block / wipe out the receiver connected to it (meaning that it's oscillation was so strong that the receiver was being blocked from receiving any other signals....note that this is sometimes confused with "overloading", but it isn't the same thing.....and, although "overloading" is getting rare these days in VHF systems, it does also occur...)
As well as have personally seen others with similar
commercial VHF and UHF pre-amp oscillations...
These are usually caused by devices going out of tolerance....and/or junction issues....not from lightning strikes (whether direct or close)...
But, whatever the cause, it does happen!!!
Also, there are numerous times when you generate receive IMD from the pre-amp....and while this usually only happens in RF crowded environs......this describes harbor areas and in/near heavy ship-traffic areas, with numerous VHF (and AIS) transmissions....
Gosh, there are many more personal experiences I could list.....but, I think I've been specific enough to prove that I'm no liar!!! (btw, I do have a blown cross-band coupler, still sitting under my desk at home....and if ya' send me about $250 - $300 cash, I'll send it to you as physical proof...
c) As for being "lazy"....
Well, since I'm the only one caring for my 94 yr old Mom, as well as still working/consulting part time, as well as attempting to have a tiny bit of a social life, and I do still get out and sail.....I find this comment to be quite rude as well...
And, specifically this week, where I have been dealing with my Mom's doctors' appointments / diagnosis.....her primary physician, oncologist, and surgeon.....all this past week....(her appointment with the surgeon is tomorrow)...
To say that all of this has taken some of my time is an understatement....not to mention that I've spent a great deal of my spare time with her, taking her mind off her diagnosis / surgery....and I'm NOT complaining at all....heck some of this "quality time" is us watching
Miami Dolphins football, so it's not really a big deal...
And, I love my Mom....my parents taught me about sailing, voyaging, cruising, adventure, etc. during the 60's and 70's....my Dad taught me celestial nav, and they both taught me to admire / respect others, especially those of different cultures/backgrounds...in our cruises when I was a kid in the 1960's, we did everything that everyone does now a days, times 10!! Including......................................... .......................
Why bother listing it all....you'd probably call me a liar anyway.....(hey, we weren't the Dashews or Pardeys, but damn few others were out there doing it in the 60's....nuf said!)
Sorry, for the digression....But, to write that I'm "lazy"??
Well, that is just out-n-out rude and insulting to me and my family!!
d) As for me implying that a sailor's spare PL-258 barrel would be corroded....sorry, but that is NOT what I meant....just listing this as information/knowledge to be aware of, before making a decision on use of an AIS "splitter"....
Quote:
Originally Posted by colemj
But you and Bill have both put forth the argument on this thread that the inclusion of two extra connectors in using a splitter puts the VHF safety at risk and is bad engineering practice. You even implied that a barrel connector, to be used in the event of a splitter failure to join a split VHF cable, was risky because of "possible corrosion".
Mark |
What I mean is that if you choose to keep one handy (in case of a "splitter failure"), then you should keep it clean and dry....(not sure how that was misunderstood...but, sorry about that!)
e) And, as for me commenting on "connectors".....
I'm the one here who has been realistic about the miniscule amount of connector loss!!!
Have you not seen the
photo???
http://www.cruisersforum.com/forums/...ld-130803.html
I have NEVER written, NOR EVER implied that the addition of two extra connectors (on the "splitter" or otherwise), introduces any measurable losses at all!!!!!!!!!!!!!!!!!!!!!!
Here again, you are further insulting me....
I do not expect a nice brief apology, and I have decided to just unsubscribe from this thread, and never return to it.....so, no need to try to impress me with any semantic argument, etc., I'm done here, and wish the original poster all my best...(and Merry Christmas!)
Rather, I just wanted to make it clear to you all that I'm neither a liar, nor lazy!
3) As for others not considering their VHF as part of their
collision avoidance system.....I think this is just a language issue....as I fully understand the ColRegs and have been doing
collision avoidance for > 40 years....
I think we agree, as it is part of the safety system, and used for short-range comms....here on this side of the Atlantic (as well as crossing the Atlantic), it is used for
communications to coordinate crossing/passing situations (what I generically called "collision avoidance"), etc....
Just a different choice of words....no worries!
4) As for VHF antennas and their VSWR....have you looked at the sweep/scan of my masthead-mounted, 1/2-wave, 3' Shakespeare end-fed SS whip???
It's right there in this thread....have a look....(if I get the time, I'll test my bimini-height, stern-rail mounted antenna, and post the results there as well...)
http://www.cruisersforum.com/forums/...ld-130803.html
And, have you read the links I posted right here, in this post???
http://www.cruisersforum.com/forums/...ml#post1986461
Fair winds...
John
Linear Mode
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