In , Skipp remembers when continues
wrote:
: Frank Gilliland wrote:
: No I wasn't. I know what I'm talking about, but you obviously don't. Notice I
: said "last-on-first-off", not "make before break". And BTW, when talking about
: relay and switch contacts, the proper terms are "shorting" and "non-shorting",
: not "make before break" and "make after break" -- just a little tidbit of info
: that will help you sound like a real tech even though you aren't.
What started your rant was my mention of hot switching of the amplifier
which was part of the original thread. You said it might have a
sequenced, arc'd or what term you'd like to use... relay. I said it does
not. In short, as shown the original (pride brand I belive) amplifier
probably hot switches RF unless you can prove otherwise.
Wrong. It does neither until someone proves otherwise. I really don't care if
the amp uses a sequenced relay or not, since it is designed for illegal use in
the US market anyway.
None of the Pride
amplifiers I have here use any type of special or sequenced relay for RF
switching.
Pride amps suck. Period. They are probably the worst designed piece-of-**** amps
ever pushed onto the ultra-gullible illegal CBer market. But most of them had
one advantage that few CB amplifiers ever had (or ever will have): they used
seperate relays for input and output. And yes, they ARE sequenced! Even the
diminutive Pride 100 had seperate, sequenced relays. And the use of seperate
relays was enough to give them a reputation for stability (never breaking into
oscillation), regardless of the fact that they would splatter up and down the
spectrum like a spark-gap transmitter.
:Your post just above is nothing special... nor is it news. Possibly
:an attempt to change the subject to power supply squence relays from TR
:switching..?
: You say that you have lots of experience with tube amps. If so, you should know
: exactly what I am talking about. But you don't. You don't have anywhere' s near
: the experience with tube amps that you claim, or else you would know that when
: you apply screen voltage without plate voltage in one of these big power tubes
: you start melting grids! And you should also know that if you don't hold the
: load on your output tank until -after- the final powers down then you are going
: to blow your receiver's front end. Sequential relays are an essential part of
: any power transmitter, whether it's tube or solid-state.
I only claim to prefer half and half in my coffee, not much more frankie.
If I or others don't give you tube amp 101 complete, you start claiming we
don't know something because it wasn't previously mentioned. Now where did
I or anyone claim anything specific about screen anode voltage
sequencing..? I mentioned an common homebrew (amateur) practice about
deriving screens from the HV supply, no magic there.
Lame excuse, Skippy. You should pick up a copy of the ARRL handbook. I'm sure
Scott can give you the card catalog number if you can't afford a copy at the
local used book store.
If you stay with one example amplifier circuit, then it's much easier to
get into specifics... I'm not even sure where you'r "pulling your load on
the output tank until after it powers down" statement from. What do you
consider "powers down" frankie..? Sequential RF relays are not an
essential part of any tube or solid state power transmitter... your going
to up the power level of the topic amplifier to some broadcast
transmitter now..?
Wrong. You ALWAYS apply plate voltage before screen voltage. It's a given. Just
like using ground for the other end of any B+ supply. Or star-grounding each RF
stage of an amplifier or receiver. When you read a schematic, some things don't
need to be mentioned, and sequential keying is one of them. That's just ONE of
the fundamentals you missed in your internet-based education.
If you'd stay on topic (like the original small rf amplifier for
example), fine. If you want to jump from amps to transmitters at various
power levels... clearly say so. I have transmitters delivering power
which have no relays at all. Everything is electronic switching... just
depends on the power level of which you reference. But goodness you like
to dance around.
Quit whining and stay on topic -- why are sequential relays "bad news"?
If you jump to larger broadcast transmitters... they are often loaded with
relays and permissive controls, but for the most part, there are no
special sequenced TR relays switching RF in the output power section. Per
the original thread that you took off dancing your tune... there is no
hot switching of rf in a typical broadcast transmitter.
DUH!!! There is no switching AT ALL in a broadcast transmitter because it's not
a transceiver! How dumb do you think CBers are? Oh, that's right, you equated
their mentality to Forrest Gump: "Life is box of chocolatte."
:Nice song and dance... but again IT'S NOT USED IN ANY CURRENT AMATEUR
:OR COMMERCIAL AMPLIFIER CIRCUIT, nor was it common in past commercial or
:amateur amplifiers.
: Single sequential relays were most certainly common in commercial
: equipment and some amateur equipment of the past, and are still used in
: some current stuff.
: Like I said, I have a box full of such relays. I'll send you some if
: you want, but you pay postage.
As stated before, I'd settle on the name of any current Amateur or
Commercial Amplifier which uses Sequential relays to switch RF...? I'd
even offer up that you could also provide the name of any broadcast or
amateur transmitter which uses your special sequential relays to switch
RF..?
I'm not a ham, but you are, and you claim to have a ****load of amps. Why don't
you mic a few contacts and post the results? But remember that I have a few
myself, and so do many people on this newsgroup -- IOW, don't post bogus data!
That was the original topic of your follow up post to my comments on
the mentioned amplifier... Sequential relays for RF t/r switching.
It's been around a lot longer than you have, and even exists in your example of
the Micor from Motorola. You want gapped contacts? I offered you a box full of
them, but for some reason you have refused.
::Other than you gassy cloud sequence story, can you provide any
::modern rf amplifier circuit using a sequence relay...
:
:: I'm willing to bet that the amplifier in question does.
:
:It doesn't...
: Did you design it? Do you have one handy and mic'ed the contacts? Or are you
: just psychic? But you may be right, since that amp isn't exactly the best
: example of RF engineering anyway.
I've had about one of most every type amplifier made through the last few
decades...
Yeah, right. You are -SO- full of **** it's not even funny.
and yes, I've had and still have a few Pride amplifiers
in my collection. For the most part, they use generic relays. Some of
their amplifier circuits are pretty nice, most of their mobile amplifiers
are crap. Every amplifier they've produced had/has shortfalls in the
designs... but so has most every brand of amplifier made. If you want to
use one, you buy it and improve it as best possible and practical.
What's your point? That you can't afford anything but Pride amps? Hey, I'll
believe THAT! What I WON'T believe is that you designed and/or built any big
amps (tube or ss) that worked! I think you have a few cheap amps that you value
ONLY because you can't afford anything else!
:: You probably won't see such a notation in any owner's or service
:: manuals since these relays are typically ordered from the manufacturer
:: with the specified gap (or 'contact delay' -- same thing). All you get
:: from a service manual is the replacement part number. Replacing one of
:: these with a general-purpose relay -without- checking the contact gaps
:: on the original can lead to some serious trouble (and I learned THAT
:: one from experience).
:
:Brand and model of said lesson device...?
: Believe it or not, I actually remember the model even though it was almost 25
: years ago -- it was a 2-channel Motorola T51GGV. I remember it well because the
: first time it came into the shop it needed a new T/R relay, which I replaced
: without knowing about the contact gapping requirements. But that darn radio came
: back to the shop several times afterwards because it kept blowing the final (a
: single 6146). That's when I got the lesson (scolding) about contact gaps from
: Stan (the shop owner).
Your talking an old Motrac era tube radio, originally designed from the
60's. You are not talking about any amateur or commercial amplifier
produced on a large scale. ... or for the most part, even a relative small
scale production for the consumer.
Your lack of experience is showing yet again. Those old radios used the circuits
most hacked by amateurs for both homebrew AND manufactured amps. Are you so
stupid to think that the big companies used circuits designed by amateurs? No,
not even close, Skippy, they used circuits designed by PROFESSIONALS, and the
amateurs copied them!
The replacement for your mentioned 60's designed radio is/was a radio with
delay A+ and A- controls and a reed relay switching 100 watts plus of RF.
Commonly called a Micor... or the Mocom 70 depend on your pocket book and
how deep you let Motorola into it.
All Motorola radios used sequential switching. Check your Micor manual and look
for the "P-T-T sequencing diagram" in the "Control Board" section. There you
will find a diagram similar to the schematic I posted. And whether the
sequencing is done with reed relays (a la Micor), seperate relays (a la Pride),
or gapped relay contacts (a la Motorola, GE, Henry, Uniden, Kenwood, Henry,
Collins...etc, etc), it all amounts to the same effect. The PROBLEM is that you
can't accept that there is, and has been for some time, another method of
sequential switching other than what you have learned from the internet! Get
over your ego trip, learn from your mistakes, and move on!
Stay in the 60's if you like... amplifier mfgrs have long since moved on
to more practical circuit which left sequential rf tr relays by the
wayside.
:Nice try at a side step dance... I was talking about your oh so popular
:sequenced relay contacts... on the same frame. Don't try to blend it into
:a sequenced relay layout. We were talking a single relay frame, not more
:than one relay.
: You can accomplish the same thing either way. With two relays (and a diode) it's
: an unbelievably simple circuit:
: http://www.aimcomm.net/sparky/sq_rly.gif
: And in case you never noticed, that's a very common circuit, even in modern
: radios with reed relays. But if you are using open-contact type relays it's much
: easier and cheaper just to gap a pair of contacts wider than the others on the
: same relay. Jeez, Skip, I can't believe that you don't know this stuff -- this
: is like high-school level electronics!
Jeez frankie, in case you hadn't noticed... much of current amateur
amplifier technology uses fast relays and electronic bias which don't
require sequenced t/r relays. A typical reed or vacuum relay is faster
than the typical driving radio/exciter. I can't believe you don't know
this stuff... :-)
So why do the same radios use delay lines for their sequential switching? And
before you whine about going off-topic, don't forget that YOU were the one who
first mentioned delay lines!
[snipage of frankies previous dance and sing, topic avoidance...)
What did you snip? I checked the previous post and it looks like you didn't snip
anything....?
: That didn't answer the question -- why are they "bad news"? Because they aren't
: "popular"? Maybe you should take a closer look at some of these un-"popular"
: amps from makers like Collins, Henry, Kenwood.... or hey, you could even check
: your copy of the ARRL handbook! I have the 1978 edition and it shows a couple
: examples of sequenced relays.
Notice the Decade... 1978 We've come a long way from 1978. Let me
repeat the question; are there any current Amplifier mfgrs using
Sequential Relays to switch RF..?
Almost all of them, including your referenced Micor. But that didn't answer the
question -- why are they "bad news"?
As a sidebar notation: The collins 30-L1, 30-S1, Henry Series and the ill
fated Kenwood TL-series of hf amplifiers did not use sequential relays for
RF switching. Many or most of the above hot switch rf, which is not good
news. That's where this all started...
Aside from the fact that triodes don't have screen grids, keep going.....
: Oh, and speaking of the ARRL handbook, notice that in every single example of HV
: power supplies where there are semiconductor rectifiers in series they use
: resistors and caps. On p.113 (1978 ed.) it has an entire section about using
: diodes in series, under the section on "Protection of Silicon Power Diodes".
: That section basically states that because diodes do not turn off at the same
: time (no matter how well matched they are), they are subject to transients that
: exceed the PRV of the diode. So the ARRL recommends using resistors to divide
: the reverse voltage equally, and capacitors to protect against unequal switching
: times. So do you think that the ARRL handbook is wrong?
No, I think that material writen in 1978 was probably pretty good in
1978, not always the best in 2003... some 25 years later. Things
change... big time.
How? Does the current ARRL handbook say something different? Does it assume that
we are all using 1n4007's that were made within the past couple years (you know,
the years when they are manufactured to such tight tolerances that they all
switch off at EXACTLY the same time?)? Or does it realize the possibility that
some of us don't have a retail account with Perfection Rectifier, INC?
:Because they are not reliable, nor are they practical, nor are they cheap.
: One relay is more reliable AND less expensive than two relays and a diode,
: don'cha think? And one relay uses less current, takes up less space, and is
: easier to replace when it fails, so how are they not practical? And if they were
: used by GE, Motorola, Uniden, and many major manufacturers for many, many years
: (and are STILL used by other companies despite your unqualified claims to the
: contrary), why are they "bad news", Skippy? They aren't. So shut your trap and
: learn something instead of bragging about your ignorance.
My original statement was about hot switching rf through the example
amplifier, your attempts to divert to some other dual relay example are
bogus.
There is no diversion, Skippy. Hot switching RF is easily avoided by sequential
switching; i.e, sequential relays.
Special sequential RF or your magic modified arc'd open frame type relays
are old technology and not used in modern equipment. By nature, they are
expensive and unreliable when compared to electronic switching (pin
diode) reed or vacuum relays used in most current Amateur Amplifiers.
Simple enough...
But the amplifier in question didn't use PIN diodes, or indicate the use of reed
or vacuum relays. Now what's your problem, Skippy?
I'm sure we'll be waiting some time for your example of special
model sequential tr (for switching rf) relays used in any modern radio
equipment. Those mechnical relays your standing behind are long gone from
the big picture.
The clock ticks louder and louder...
You seem to have an answer for everything else (except why sequential relays are
"bad news"), so why do some manufacturers still use open-contact relays?
"Your trap" seems to be shut on any current example..? what's up with
that frankie..?
Why are sequential relays "bad news", Skippy?
Onward...
The number of relays required to complete the TR function is another
whole topic.
Don't pull that off-topic crap -- why are sequential relays "bad news"? Address
the issue, Skippy!
I do not care to bring in your latest off topic
number of relay diversion as it was never part of the original thread.
Stay on track frankie.
Gladly. Why are sequential relays "bad news"?
:There is a reason few if any amplifier - radio mfgrs are (might use a)
:using sequential relay(s). You'd better jump from this "Titanic Topic"
:before you go down with the ship.
: No, YOU better start paying attention to how these things are actually designed
: and built! The reason (and I said this before) is because they are being
: replaced by reed relays in sequential circuits. But not every manufacturer uses
: reed relays. Some still use open-contact relays, such as the amp that YOU used
: for an example.
The original amplifier circuit which started all this, is still hot
switching RF.
Possible, yet unproven. Regardless, why are sequential relays "bad news"?
Your original followup to my mention of said suggested the
amplifier might have had a sequential relay (or similar function) TR
switching RF. I claim is does not and I stand by it until you prove
otherwise.
Then it shall remain unproven. Still, why are sequential relays "bad news"?
By the way Mr Technology... since you're paying attention of course..
A typical "properly designed" amateur amplifier with reed relay switching
probably doesn't have to have a sequential relay circuit, the reed relay
is often faster than any typical Amateur Radio driving said amplifier.
The primary purpose of sequential relays is to provide the proper sequence
between RX RF, audio input, final drive, final load and final power input (and
screen bias for pentode/tetrode finals). Screw up the sequence and you can screw
up the tranceiver. Now, why are sequential relays "bad news", Skippy?
:I guess all the keyed A+ and A- used by companies like Motorola (for
:decades) prefer the harder route. Come on now frankie...
: No. After the old tube monsters went extinct, Motorola took a different path and
: built some radios that put the relay sequencing into the mic switch, which
: wasn't too popular because the mics weren't interchangeable between radios. But
: many shops tried anyway, resulting in a lot of bad radios, which is one reason
: why their radios sucked for a long time. The Mocom line used a single sequenced
: relay, which was made just before they began using sequenced reed relays (using
: circuits similar to what I provided in the schematic).
Motorola produced high powered tube amplifiers through the 80's and into
the 90's.
So?
These magic radios you claim Motorola produced with sequential TR - RF
switching... how about a model name...? In the commercial world, they
were not long term reliable, they were expensive and they fell by the
wayside when the technology moved on... some 25 or more years ago..?
All of them, or haven't you been paying attention?
: But you should know all this already because you are a radio tech, right?
Yeah, just by luck I worked for a Motorola Service Station for "a few
years", it also happens to be one of the largest in the Nation... still.
Then why haven't you learned anything about sequential relays? What did you do
there -- mop the floors in the heads?
So after you abandon your Sequential relay statements and try to merge
your current foot in mouth position into some type of sequential reed
relay circuit... how about you get back on track. As in current
amplifier or radio technology... some 20 to 25 year later.
You keep whining about "dated" technology, yet you don't even know what was used
in the past OR the present.
:I believe the original subject was an Amplifier... was it not..? The
:last radio with a t/r relay was made ...? .... years ago..? ... decades
:ago..?
: T/R relays are still used today -- did you forget about that amplifier we were
: talking about?
Was a pride right..? if it was made as shown in the original diagram, it
still hot switches RF as I first mentioned. You claim it doesn't and you
are wrong. Nothing has changed...
Wrong. Most of Pride's amps used seperate relays in a mode where one relay
controlled the other -- sequenced relays.
:: Reed relays don't carry RF very well. And they certainly don't carry
:: power because it tends to vaporize the Hg and destroy the relay. They
:: are usually only used for low-voltage DC and audio switching. But you
:: knew that, didn't you Skippy?
:
:I'm laughing at you big time here frankie.. I guess decades of Motorola,
:GE, EF Johnson, Aerotron rf amplifier and radio switching with reed relays
:doesn't prove anything.
: By "power" I meant kilowatts, but I'll let you gloat for a while anyway because
: I should have stated myself more clearly.
The original amplifier was not at the kilowatt level.... but just for the
sake of others reading this. The typical multi kilowatt level amateur
amplifier uses reed relay switching on the input and vacuum relay
switching on the output. In some cases, vacuum relays are used on both the
input and the output. They handle the RF well and they are very fast...
fast enough that the driving radio is most often not subject to rf hot
switching.
Nobody said they weren't fast. I said they are lossy; and they are when compared
to a good open-contact relay designed for power RF. Reed relays are cheaper and
smaller. If given a choice, I'll spend a couple extra bucks for a -good- relay.
: I guess its time I went and threw out the large
:box of reed T/R relays I have from salvaged high power Motorola Micor
:Radio Equipment.
: Oh, hey, remember your question above? "The last radio with a t/r relay was made
: ...? .... years ago..? ... decades ago..?" I think you answered your own
: question, Skippy.
Actually...
I was hoping you'd comment on your statement that "reed relays don't carry
RF well..." but you avoided it big time.
They don't. They are used because they are cheap and small.
: I got some nice/neat pictures of their very common
:yellow RF switching (reed) relay I could send if you'd like to view them
:while eating your crow.
: It's more fun to see how differently you react when you know for a fact
: that you are right, as opposed to 99% of the time when you are
: shoveling technical voodoo based on your misunderstanding of the
: fundamentals and your lack of education
: and experience, or plagiarizing some ham that shares your ignorance. It's almost
: like you jump out of your seat and lapse into convulsions when you can finally
: nail me on something! I should put out some intentional misinformation just to
: jerk your chain once in a while!
I feel humbled knowing your opinion frankie...
You should.
but you are still wrong
about the hot switching comments you made.
Why are sequential relays "bad news"?
If you weren't so bitter and mean, people might like you better... even
with your ego as bad as it is.
Quit trying to drag this off-topic and answer the question: Why are sequential
relays "bad news"?
:I appreciate your concern frankie, but you have me confused with someone
:who really cares about what you post.
: ...uh huh. That's why we are having this conversation, right?
Mostly to get the proper facts out...
You have had ample opportunity to disclose as many facts as you want, but all
you seem willing to provide is your opinion backed up with no more than two
websites, both of which were quickly dismissed -- one because it contradicts
your own opinions, and the other because of both theoretical and mathematical
inaccuracies. Where are your "facts", Skippy?
people make mistakes, both you and
I. I call you on some of yours, you call me on some of mine. If you
weren't so bitter about it, it might be a lot more fun. You wouldn't get
that knot in your stomach and have your blood pressure jump up when you
see that I've posted a follow up.
The difference, Skippy, is that when I make a mistake I admit it. When you make
a mistake it's because you have no clue what you are talking about and are
trying to sound like you are something you aren't -- technically competent.
Unfortunately, your mistakes occur with just about everything you say, and since
you can't admit them, you compound your ineptitude by piling on more of your BS
theories. I'm not saying that you are incapable of understanding any of this
stuff, but that you are too lazy to learn it the right way. Forget the internet
and read some books written and published with some authority. Go visit your
local public library if you can't afford the books. But for crying out loud,
quit professing your ignorance by trying to top someone with five years of
college and over 25 years experience in the field! Hey, I don't know everything,
but I sure as hell know more than you ever will, and I certainly know how to
fill in any gaps in my knowledge base. You don't even HAVE a knowledge base. Get
one. Then we'll argue. Until then, you will be treated just like any other
blowhard keyclown tech-wannabe.
:Hopefully Brian did not go for your dated relay information. Arcing /
:bending relay contacts for use in RF amplifiers is bad news.
: Even though it's a method that has been used successfully for almost a century,
: and still used even today, why is it "bad news", Skippy? Why can't you answer
: that simple little question?
Simple enough...
Compared to the alternatives like pin diode, reed and vacuum relay, it's
very unreliable.
Wrong. The reliability of the electro-mechanical relay is a tough act to beat.
While the vacuum relay reduces arcing of the contacts, that only extends the
life of the contacts. The reed relay is based on the same principle, but it's
advantages are only it's small size and low cost. The PIN diode has severe power
limitations, and is highly vulnerable to transient peaks and surges. And when
you consider that an open-contact relay is easily maintained just by cleaning
the contacts, and replaced with the simplicity of a vacuuum tube, there are FEW
devices that can be considered to be as reliable.
It's also more expensive than some of the circuits which
replaced it.
You get what you pay for.
Now your turn frankie.... who's bending relay contacts these days and
where can we find it done..?
Beats me. But if you want to know who is using sequential relays, pick just
about anybody in the list. How they implement them is strictly a matter for
their engineers. For the amateur building an amp using open-contact relays, I
would recommend gapping the contacts on one relay as one method of sequencing
the switching, and I know that some do it that way. For manufacturing, I don't
know why anyone would use an open-contact relay except for RF power switching.
Frankly, I'm suprised how many use reed relays and not open-contact relays for
RF power switching. But that's their problem because I don't use those radios or
recommend them to any of my customers. If you saw the specs for yourself, you
wouldn't either.
: Wasn't
:even great back in the 50's, 60's and 70's. Bad habits die hard... you
:prove that quite a bit in your posts.
: I guess fire, gears, metallurgy, and the wheel are some of those 'bad habits'
: that use "dated technology", huh? Of course let's not forget that the internal
: combustion engine and the airplane have been around for a century, so they must
: also be "dated technology", right? But wait.... radio is over a century old,
: too... by golly, even RADIO is "dated technology"! So why the hell are you using
: it, Skippy?
Simple, its fun and pays good money.
Frankie... plasma is now common,
It always has been -- it's called 'fire'.
gears are now complex,
Do you own a bicycle?
metallurgy now
produces exotic blends and alloys
60/40 solder = 60% lead and 40% tin (or is it the other way around?)
and the wheel spins over hundreds of
thousands of rpm in turbine units.
Not on -my- truck!
Let's not forget you daddy's Oldsmobile
looks nothing like a common auto and cloth covered airplanes are not
common place in commercial aircraft mfgr.
Check the magazine rack at your local library or grocery store.
Time for you to simply enjoy your crow sandwich and move on... it's 2003
So? People still use low-tech devices like wheel-barrows, matches, .... heck,
even alcohol has been around for thousands of years and still works just the
same! Do you barbecue with charcoal or propane (yuk!)? Is the fabric in the
clothing you wear not made on a loom? And I think that even down there in
granola-land that boats float based on the principle of Archimedes law of
displacement. Just because technology is "dated" doesn't mean it's "bad news".
It's been fun for the most part.
"73's and good luck in the contest"
skipp
Read a book.
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