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This circuit is not going to perform 4 watts is it?
http://www.electronics-lab.com/projects/rf/021/index.html
too simple to be true
No chance.This circuit is not going to perform 4 watts is it?
No.This circuit is not going to perform 4 watts is it?
http://www.electronics-lab.com/projects/rf/021/index.html
Mike Bates wrote:
This circuit is not going to perform 4 watts is it?
http://www.electronics-lab.com/projects/rf/021/index.html
No.
See http://www.electronics-lab.com/projects/rf/001/index.html
you could, in theory, get 4W out of the thing -- but the inevitableThis circuit is not going to perform 4 watts is it?
http://www.electronics-lab.com/projects/rf/021/index.html
too simple to be true
Assuming that you can get enough power out of that funky oscillator then
You get 45 watts out with 25 watts plate dissipation by running at 65%I also know this is no way in the world that this is going to perform 45W
http://www.electronics-lab.com/projects/rf/019/index.html
The 807's maximum plate dissapation is about 25watts.
how do you get 45watts out of 25watts?
im looking for a good performing, but simple (im limited to radio shack
parts) fm or am transmitter. Am is a better choice, since there are about 3
or 4 i can pick up only. there are a ton of FM stations.
I'd say about 750mW at 16V in. Any takers?.kinda figured that.
id say about 100mw at best.
807 is a triode. I have no idea what an AYXNIA is.I also know this is no way in the world that this is going to perform 45W
http://www.electronics-lab.com/projects/rf/019/index.html
The 807's maximum plate dissapation is about 25watts.
how do you get 45watts out of 25watts?
Tim Wescott answered this one for you, but it's not an 807. The
Oh, easily. I wouldn't be surprised if you could a good"Mike Bates" <nospam@nospam.com> wrote in message
news:Ed6md.15941$5n3.10887@fe2.columbus.rr.com...
kinda figured that.
id say about 100mw at best.
I'd say about 750mW at 16V in. Any takers?.
Well, rats! Of course you're right. Now I even remember the 807W/5933,Rich Grise wrote:
On Mon, 15 Nov 2004 17:08:38 +0000, Mike Bates wrote:
I also know this is no way in the world that this is going to perform 45W
http://www.electronics-lab.com/projects/rf/019/index.html
The 807's maximum plate dissapation is about 25watts.
how do you get 45watts out of 25watts?
Tim Wescott answered this one for you, but it's not an 807. The
807 is a triode. I have no idea what an AYXNIA is.
And I also have no idea why they'd want to transmit AM in the FM
broadcast band, unless that's supposed to be a reactance modulator,
in which case it's a really crappy one.
Good Luck!
Rich
The 807 (at least without the apostrophe) is a beam tetrode, similar to
the 6L6 but heftier and good up to 60MHz before it starts dropping off
Thanks!-- you can use it at reduced input at 100MHz, but I don't think you can
get 45W out of it as a self-excited oscillator; I'm not even sure you
could put 45W _into_ it as a self-excited oscillator at that frequency
and have the plate stay in one piece.
Any time you modulate an oscillator you'll get FM _and_ AM -- in this
case you'll have both, so you can choose which you want to call it.
I think you hit the nail on the head. I once ran a 2N2219 at 28 MHz off aHi,
This circuit is not going to perform 4 watts is it?
http://www.electronics-lab.com/projects/rf/021/index.html
too simple to be true
There is more than one method of rating a transmitter's power
and simple DC input is a common way to do that. Seen this way, in
the circuit given the power input lies between 1.2W and 6.4W and
4W is then a conservative figure. How long it would last, and how
efficient it would be, is another story.
Radio amateurs are required to use this method because it is
simple to implement and relieves them of the necessity of having
accurate power output meters. It must be presumed that here the
builder checked the supply voltage and current before posting
them.
However, he must have kept it in the refrigerator he specifies
and used a frequency-agile receiver to track it as it drifted up
and down the band.
Cheers - Joe
The 807, 6146 and EL34 are all beam power tetrodes with similar power"Joe McElvenney" <ximac@btinternet.com> wrote in message
news:VA.00000048.002614b7@btinternet.com...
Hi,
This circuit is not going to perform 4 watts is it?
http://www.electronics-lab.com/projects/rf/021/index.html
too simple to be true
There is more than one method of rating a transmitter's power
and simple DC input is a common way to do that. Seen this way, in
the circuit given the power input lies between 1.2W and 6.4W and
4W is then a conservative figure. How long it would last, and how
efficient it would be, is another story.
I think you hit the nail on the head. I once ran a 2N2219 at 28 MHz off a
20V supply, and got a couple of W out of it. Would not expect anywhere that
much at 100 MHz. First thing it would need is a BIG heat sink.
On the tube amp, I have the 807 data sheet, and that looks like it may
legally do 20W out at 100MHz. Somebody mentioned the 6146, which sort of
replaced the 807, 50 some years ago. It will do around 40W at 100 MHz, but
has nothing in common with the 807. Different size, and different number of
pins. I don't know where the EL34, or equivalent, comes in. I thought that
was a single ended audio tube.
Tam
Tam posted:
(snip)
On the tube amp, I have the 807 data sheet, and that looks like it may
legally do 20W out at 100MHz. Somebody mentioned the 6146, which sort of
replaced the 807, 50 some years ago. It will do around 40W at 100 MHz,
but
has nothing in common with the 807. Different size, and different number
of
pins. I don't know where the EL34, or equivalent, comes in. I thought that
was a single ended audio tube.
In the 50s, when the Novice license began, they were permitted to use AM
on 2
Meters. The Harvey Wells TBS50 transmitter helped fill that market. It's
807
final could provide 5 Watts input at 145 MHz. On HF it would coast at
50W.
Don
10MHz. A 2N3866 would be a classic for this application (and yes, itso, are we saying that tube design would work?
BTW. I want no more than 500mw to a watt out of that solid state FM
transmitter. Will that circuit do about 500mw with 2n3053? its rated at
100mhz, and I have 2 of those on hand. If i build that circuit with those 2
transistors, and should I expect about 500mw to a watt? or so?
im just looking for a simple easily makable FM or AM transmitter that is
about 1 to 4 watts or so.
i already have a 1 watt AM transmitter, but it dont get crap for range. 30
feet at most.
An f_t of 100MHz means that you don't want to try to use it above about
Mike Bates wrote:
i had some time, and went ahead and built the circuit.
its a little bit funky to tune, but im astonished how it performs.
Well, so much for the accumulated wisdom of experts.
i used those transistors, its oscillating around 108mhz, and im putting a
good solid watt out of it according to the SWR/watt meter. only problem
is,
with those cheap ol radios from the dollar store, there aint an open spot
on
it.
Feel up the transistors -- if you can't hold your finger on them without
saying "ouch" they need heatsinking.
You realize, of course, that anything unlicenced in that band, over a few
10s of milliwatts, is not legal. you'll only have problems if you bother
somebody enough for them to call the FCC, but there you are.
the digital PLL tuner has some free spots, but they wont work without
bleedover on cheap radios.
next thing, is i need to get a harmonics supressor, because its full of
it.
ARRL handbook.
another thing i noticed to, is the fidelity is clear and sharp when the
radio is tuned "near" the lockon freq.
if i put the radio on the actual lockon frequency of the transmitter, is
all
distorted. its either overloading the radio, or something else is wrong.
I have no idea - but you might try reducing your audio in to reduce your
modulation.
JohnTim Wescott
Wescott Design Services
http://www.wescottdesign.com
No, an 807 (note: no apostrophe - "807" is the whole type number!) startsMike Bates wrote:
I also know this is no way in the world that this is going to perform 45W
http://www.electronics-lab.com/projects/rf/019/index.html
The 807's maximum plate dissapation is about 25watts.
how do you get 45watts out of 25watts?
im looking for a good performing, but simple (im limited to radio shack
parts) fm or am transmitter. Am is a better choice, since there are about 3
or 4 i can pick up only. there are a ton of FM stations.
You get 45 watts out with 25 watts plate dissipation by running at 65%
plate efficiency or better. At 30MHz you could definitely do so with an
'807 as an amplifier, I'm not sure you could at 100MHz, or with the tube
used as a power oscillator.
Well, also notice T2 in the first one:Don't get me wrong about either of these circuits: they won't make you
happy. But either of them may be made to work for a little while, if
you're lucky, before the smoke comes out.
I was commenting on the 807 posts, not an FM transmitter.Tam posted:
(snip)
On the tube amp, I have the 807 data sheet, and that looks like it may
legally do 20W out at 100MHz. Somebody mentioned the 6146, which sort of
replaced the 807, 50 some years ago. It will do around 40W at 100 MHz,
but
has nothing in common with the 807. Different size, and different number
of
pins. I don't know where the EL34, or equivalent, comes in. I thought that
was a single ended audio tube.
In the 50s, when the Novice license began, they were permitted to use AM
on 2
Meters. The Harvey Wells TBS50 transmitter helped fill that market. It's
807
final could provide 5 Watts input at 145 MHz. On HF it would coast at
50W.
Don
Mike Bates wrote:
so, are we saying that tube design would work?
BTW. I want no more than 500mw to a watt out of that solid state FM
transmitter. Will that circuit do about 500mw with 2n3053? its rated at
100mhz, and I have 2 of those on hand. If i build that circuit with
those 2
transistors, and should I expect about 500mw to a watt? or so?
im just looking for a simple easily makable FM or AM transmitter that is
about 1 to 4 watts or so.
i already have a 1 watt AM transmitter, but it dont get crap for range.
30
feet at most.
An f_t of 100MHz means that you don't want to try to use it above about
10MHz. A 2N3866 would be a classic for this application (and yes, it
only has an f_t of 500MHz, but it's made for UHF).
http://www.ramseyelectronics.com/ should have a number of kits that
would work for you, and there are other kit vendors. They tend to be a
bit cheezy, but if give it some effort you can get them to work.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com