strange oscillator...

S

server

Guest
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
SHEET 1 1220 836
WIRE 528 112 288 112
WIRE 288 144 288 112
WIRE 288 272 288 224
WIRE 528 288 528 112
WIRE 400 368 288 368
WIRE 480 368 400 368
WIRE 400 416 400 368
WIRE 288 528 288 368
WIRE 400 560 400 496
WIRE 432 560 400 560
WIRE 528 560 528 384
WIRE 528 560 496 560
WIRE 400 608 400 560
WIRE 528 656 528 560
WIRE 288 720 288 592
WIRE 400 720 400 688
WIRE 400 720 288 720
WIRE 400 816 400 720
WIRE 528 816 528 736
FLAG 288 272 0
FLAG 528 816 0
FLAG 400 816 0
SYMBOL voltage 288 128 R0
WINDOW 0 68 58 Left 2
WINDOW 3 59 97 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName Vd
SYMATTR Value 2.5
SYMBOL mesfet 480 288 R0
WINDOW 0 86 36 Left 2
WINDOW 3 62 64 Left 2
SYMATTR InstName Z2
SYMATTR Value SAV541
SYMBOL ind 416 512 R180
WINDOW 0 70 75 Left 2
WINDOW 3 61 43 Left 2
SYMATTR InstName L1
SYMATTR Value 2.5n
SYMBOL current 528 656 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName I1
SYMATTR Value 10m
SYMBOL cap 272 528 R0
WINDOW 0 -59 14 Left 2
WINDOW 3 -61 49 Left 2
SYMATTR InstName C1
SYMATTR Value 2.5p
SYMBOL ind 416 704 R180
WINDOW 0 70 75 Left 2
WINDOW 3 62 41 Left 2
SYMATTR InstName L2
SYMATTR Value 2.5n
SYMBOL cap 496 544 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C2
SYMATTR Value 5p
TEXT -96 272 Left 2 !.tran 50n uic
TEXT -232 368 Left 2 !.MODEL SAV541 NMF(vto=0.08, Beta=0.6,\\n+
Lambda=0.07, Alpha=4 B=0.8, Pb=0.7,\\n+ Cgs=0.997E-12, Cgd=0.176E-12,
Rd=0.084,\\n+ Rs=0.054, Kf=5e-11, Af=2)
TEXT -144 152 Left 2 ;SAV-541 2L Oscillator
TEXT -120 216 Left 2 ;JL Feb 1 2022





--

I yam what I yam - Popeye
 
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
SHEET 1 1220 836
WIRE 528 112 288 112
WIRE 288 144 288 112
WIRE 288 272 288 224
WIRE 528 288 528 112
WIRE 400 368 288 368
WIRE 480 368 400 368
WIRE 400 416 400 368
WIRE 288 528 288 368
WIRE 400 560 400 496
WIRE 432 560 400 560
WIRE 528 560 528 384
WIRE 528 560 496 560
WIRE 400 608 400 560
WIRE 528 656 528 560
WIRE 288 720 288 592
WIRE 400 720 400 688
WIRE 400 720 288 720
WIRE 400 816 400 720
WIRE 528 816 528 736
FLAG 288 272 0
FLAG 528 816 0
FLAG 400 816 0
SYMBOL voltage 288 128 R0
WINDOW 0 68 58 Left 2
WINDOW 3 59 97 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName Vd
SYMATTR Value 2.5
SYMBOL mesfet 480 288 R0
WINDOW 0 86 36 Left 2
WINDOW 3 62 64 Left 2
SYMATTR InstName Z2
SYMATTR Value SAV541
SYMBOL ind 416 512 R180
WINDOW 0 70 75 Left 2
WINDOW 3 61 43 Left 2
SYMATTR InstName L1
SYMATTR Value 2.5n
SYMBOL current 528 656 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName I1
SYMATTR Value 10m
SYMBOL cap 272 528 R0
WINDOW 0 -59 14 Left 2
WINDOW 3 -61 49 Left 2
SYMATTR InstName C1
SYMATTR Value 2.5p
SYMBOL ind 416 704 R180
WINDOW 0 70 75 Left 2
WINDOW 3 62 41 Left 2
SYMATTR InstName L2
SYMATTR Value 2.5n
SYMBOL cap 496 544 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C2
SYMATTR Value 5p
TEXT -96 272 Left 2 !.tran 50n uic
TEXT -232 368 Left 2 !.MODEL SAV541 NMF(vto=0.08, Beta=0.6,\\n+
Lambda=0.07, Alpha=4 B=0.8, Pb=0.7,\\n+ Cgs=0.997E-12, Cgd=0.176E-12,
Rd=0.084,\\n+ Rs=0.054, Kf=5e-11, Af=2)
TEXT -144 152 Left 2 ;SAV-541 2L Oscillator
TEXT -120 216 Left 2 ;JL Feb 1 2022
Click to expand...

Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet
 
piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
SHEET 1 1220 836
WIRE 528 112 288 112
WIRE 288 144 288 112
WIRE 288 272 288 224
WIRE 528 288 528 112
WIRE 400 368 288 368
WIRE 480 368 400 368
WIRE 400 416 400 368
WIRE 288 528 288 368
WIRE 400 560 400 496
WIRE 432 560 400 560
WIRE 528 560 528 384
WIRE 528 560 496 560
WIRE 400 608 400 560
WIRE 528 656 528 560
WIRE 288 720 288 592
WIRE 400 720 400 688
WIRE 400 720 288 720
WIRE 400 816 400 720
WIRE 528 816 528 736
FLAG 288 272 0
FLAG 528 816 0
FLAG 400 816 0
SYMBOL voltage 288 128 R0
WINDOW 0 68 58 Left 2
WINDOW 3 59 97 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName Vd
SYMATTR Value 2.5
SYMBOL mesfet 480 288 R0
WINDOW 0 86 36 Left 2
WINDOW 3 62 64 Left 2
SYMATTR InstName Z2
SYMATTR Value SAV541
SYMBOL ind 416 512 R180
WINDOW 0 70 75 Left 2
WINDOW 3 61 43 Left 2
SYMATTR InstName L1
SYMATTR Value 2.5n
SYMBOL current 528 656 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName I1
SYMATTR Value 10m
SYMBOL cap 272 528 R0
WINDOW 0 -59 14 Left 2
WINDOW 3 -61 49 Left 2
SYMATTR InstName C1
SYMATTR Value 2.5p
SYMBOL ind 416 704 R180
WINDOW 0 70 75 Left 2
WINDOW 3 62 41 Left 2
SYMATTR InstName L2
SYMATTR Value 2.5n
SYMBOL cap 496 544 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C2
SYMATTR Value 5p
TEXT -96 272 Left 2 !.tran 50n uic
TEXT -232 368 Left 2 !.MODEL SAV541 NMF(vto=0.08, Beta=0.6,\\n+
Lambda=0.07, Alpha=4 B=0.8, Pb=0.7,\\n+ Cgs=0.997E-12, Cgd=0.176E-12,
Rd=0.084,\\n+ Rs=0.054, Kf=5e-11, Af=2)
TEXT -144 152 Left 2 ;SAV-541 2L Oscillator
TEXT -120 216 Left 2 ;JL  Feb 1   2022






Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet


With no coupling, it\'s a species of Colpitts--it\'s only the tank Q that
Click to expand...
does the impedance transformation, with no help from the transformer
action of the mutual inductance.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com
 
On Tue, 1 Feb 2022 10:59:09 -0500, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.



Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet


With no coupling, it\'s a species of Colpitts--it\'s only the tank Q that
does the impedance transformation, with no help from the transformer
action of the mutual inductance.

Cheers

Phil Hobbs
Click to expand...

I was just fooling around. What I really want is a 1.5 GHz oscillator
with two antiphase outputs. A MMIC might be a good gain element.



--

I yam what I yam - Popeye
 
On 01/02/2022 3:47 pm, piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
SHEET 1 1220 836
WIRE 528 112 288 112
WIRE 288 144 288 112
WIRE 288 272 288 224
WIRE 528 288 528 112
WIRE 400 368 288 368
WIRE 480 368 400 368
WIRE 400 416 400 368
WIRE 288 528 288 368
WIRE 400 560 400 496
WIRE 432 560 400 560
WIRE 528 560 528 384
WIRE 528 560 496 560
WIRE 400 608 400 560
WIRE 528 656 528 560
WIRE 288 720 288 592
WIRE 400 720 400 688
WIRE 400 720 288 720
WIRE 400 816 400 720
WIRE 528 816 528 736
FLAG 288 272 0
FLAG 528 816 0
FLAG 400 816 0
SYMBOL voltage 288 128 R0
WINDOW 0 68 58 Left 2
WINDOW 3 59 97 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName Vd
SYMATTR Value 2.5
SYMBOL mesfet 480 288 R0
WINDOW 0 86 36 Left 2
WINDOW 3 62 64 Left 2
SYMATTR InstName Z2
SYMATTR Value SAV541
SYMBOL ind 416 512 R180
WINDOW 0 70 75 Left 2
WINDOW 3 61 43 Left 2
SYMATTR InstName L1
SYMATTR Value 2.5n
SYMBOL current 528 656 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName I1
SYMATTR Value 10m
SYMBOL cap 272 528 R0
WINDOW 0 -59 14 Left 2
WINDOW 3 -61 49 Left 2
SYMATTR InstName C1
SYMATTR Value 2.5p
SYMBOL ind 416 704 R180
WINDOW 0 70 75 Left 2
WINDOW 3 62 41 Left 2
SYMATTR InstName L2
SYMATTR Value 2.5n
SYMBOL cap 496 544 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C2
SYMATTR Value 5p
TEXT -96 272 Left 2 !.tran 50n uic
TEXT -232 368 Left 2 !.MODEL SAV541 NMF(vto=0.08, Beta=0.6,\\n+
Lambda=0.07, Alpha=4 B=0.8, Pb=0.7,\\n+ Cgs=0.997E-12, Cgd=0.176E-12,
Rd=0.084,\\n+ Rs=0.054, Kf=5e-11, Af=2)
TEXT -144 152 Left 2 ;SAV-541 2L Oscillator
TEXT -120 216 Left 2 ;JL  Feb 1   2022






Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet
Click to expand...

Found the book online, p145-146 were what I was thinking of ...

<https://www.qsl.net/pa2efr/manuals/Doc/Practical%20Oscillator%20Handbook%201997-Irving%20M%20Gottlieb.pdf>

piglet
 
On Tue, 1 Feb 2022 16:17:15 +0000, piglet <erichpwagner@hotmail.com>
wrote:
Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet




Found the book online, p145-146 were what I was thinking of ...

https://www.qsl.net/pa2efr/manuals/Doc/Practical%20Oscillator%20Handbook%201997-Irving%20M%20Gottlieb.pdf

piglet
Click to expand...

Nice. It\'s from 1997 but includes oldies like thyratrons, spark gaps,
tunnel diodes.



--

I yam what I yam - Popeye
 
On 2/1/2022 11:07 AM, jlarkin@highlandsniptechnology.com wrote:
On Tue, 1 Feb 2022 10:59:09 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.



Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet


With no coupling, it\'s a species of Colpitts--it\'s only the tank Q that
does the impedance transformation, with no help from the transformer
action of the mutual inductance.

Cheers

Phil Hobbs

I was just fooling around. What I really want is a 1.5 GHz oscillator
with two antiphase outputs. A MMIC might be a good gain element.
Click to expand...

What about cross-coupled ECL-type oscillator
 
On 2022-02-01 16:27, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
[Deleted...]
Click to expand...

To me, this classifies as a Hartley, because it has two L\'s
and one C as its tank circuit. The fact that the L\'s aren\'t
coupled, to my mind, is only a minor point.

Jeroen Belleman
 
On 2022-02-01 16:59, Phil Hobbs wrote:
piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
[Deleted ... ]

With no coupling, it\'s a species of Colpitts--it\'s only the tank Q that
does the impedance transformation, with no help from the transformer action of the mutual inductance.

Cheers

Phil Hobbs
Click to expand...

To me, a Colpitts has two C\'s and one L in its tank. This one doesn\'t.
A capacitive divider is also an impedance transformer.

Jeroen Belleman
 
On Tue, 1 Feb 2022 12:05:49 -0500, bitrex <user@example.net> wrote:

On 2/1/2022 11:07 AM, jlarkin@highlandsniptechnology.com wrote:
On Tue, 1 Feb 2022 10:59:09 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.



Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet


With no coupling, it\'s a species of Colpitts--it\'s only the tank Q that
does the impedance transformation, with no help from the transformer
action of the mutual inductance.

Cheers

Phil Hobbs

I was just fooling around. What I really want is a 1.5 GHz oscillator
with two antiphase outputs. A MMIC might be a good gain element.

What about cross-coupled ECL-type oscillator
Click to expand...

I could persuade a diff-in-out ecl gate or comparator to oscillate,
but I\'d have to try it. I don\'t have Spice models for those.

I might get lucky and just connect a diff gate into itself, inverted.
and watch it oscillate. Hey good idea! Might be fun to try.

A MMIC is a great gain element, but it\'s basically 50 ohms in and out,
the ideal tank Q killer. The best MMIC ocillator is probably
delay-line, which will give me antiphase outputs. Again, gotta solder
to test that.

I wish ADI would include their ADCMP parts in LT Spice.



--

I yam what I yam - Popeye
 
Jeroen Belleman wrote:
On 2022-02-01 16:59, Phil Hobbs wrote:
piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com wrote:
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
[Deleted ... ]

With no coupling, it\'s a species of Colpitts--it\'s only the tank Q that
does the impedance transformation, with no help from the transformer
action of the mutual inductance.


To me, a Colpitts has two C\'s and one L in its tank. This one doesn\'t.
A capacitive divider is also an impedance transformer.
Click to expand...

Not without the resonance, it isn\'t. The input is at the tap and the
output is at the top of the tank, so it isn\'t a voltage divider.

The math of a real Hartley is different from the Colpitts case, but with
uncoupled inductors it\'s the same except for the sign of the reactance.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com
 
On 2022-02-01 19:44, Phil Hobbs wrote:
Jeroen Belleman wrote:
On 2022-02-01 16:59, Phil Hobbs wrote:
piglet wrote:
On 01/02/2022 3:27 pm, jlarkin@highlandsniptechnology.com
wrote:
Not actually a Hartley, bacause the Ls are not coupled.

Version 4
[Deleted ... ]

With no coupling, it\'s a species of Colpitts--it\'s only the tank
Q that does the impedance transformation, with no help from the
transformer action of the mutual inductance.


To me, a Colpitts has two C\'s and one L in its tank. This one
doesn\'t. A capacitive divider is also an impedance transformer.

Not without the resonance, it isn\'t. The input is at the tap and the
output is at the top of the tank, so it isn\'t a voltage divider.

The math of a real Hartley is different from the Colpitts case, but
with uncoupled inductors it\'s the same except for the sign of the
reactance.

Cheers

Phil Hobbs
Click to expand...

The concepts of input and output are somewhat slippery in oscillators.
One could choose any or none of the three terminals of a transconductance
gain element as common, and inputs and outputs move about as a result. My
point is that two of the three reactances that make up the tank are of
the same sign, and one is opposite, and the low-Z node of the gain block
connects to the node where the two equal-sign reactances connect. It\'s
easier to draw than to describe.

The signs of the reactances are to me what makes the difference between
Colpitts and Hartley oscillators.

Jeroen Belleman
(Whose oscillators oscillate and whose amplifiers amplify. Usually,
anyway. :) )
 
On Tue, 01 Feb 2022 09:00:07 -0800, jlarkin@highlandsniptechnology.com
wrote:

On Tue, 1 Feb 2022 16:17:15 +0000, piglet <erichpwagner@hotmail.com
wrote:

Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet




Found the book online, p145-146 were what I was thinking of ...

https://www.qsl.net/pa2efr/manuals/Doc/Practical%20Oscillator%20Handbook%201997-Irving%20M%20Gottlieb.pdf

piglet

Nice. It\'s from 1997 but includes oldies like thyratrons, spark gaps,
tunnel diodes.
Click to expand...

Gottlieb\'s \'Understanding Oscillators\' was in its 3rd Ed in 1971.

RL
 
On Tue, 01 Feb 2022 09:00:07 -0800, jlarkin@highlandsniptechnology.com
wrote:

On Tue, 1 Feb 2022 16:17:15 +0000, piglet <erichpwagner@hotmail.com
wrote:

Yes, decades ago I built something similar using an NPN BJT at kHz
frequencies. I used two molded chokes and had initially them loose
coupled but was amazed that I could separate them or re-orient so there
was no mutual couplling and still got oscillation.

I think Irving Gottlieb described three types of Hartley in his
Oscillator Handbook and this is one of his \"type 2\" Hartleys, there is
no mutual coupling and the action is negative resistance.

piglet




Found the book online, p145-146 were what I was thinking of ...

https://www.qsl.net/pa2efr/manuals/Doc/Practical%20Oscillator%20Handbook%201997-Irving%20M%20Gottlieb.pdf

piglet

Nice. It\'s from 1997 but includes oldies like thyratrons, spark gaps,
tunnel diodes.
Click to expand...

First published 1970. 4th Ed ?

RL
 
On Tuesday, February 1, 2022 at 8:08:02 AM UTC-8, jla...@highlandsniptechnology.com wrote:

I was just fooling around. What I really want is a 1.5 GHz oscillator
with two antiphase outputs. A MMIC might be a good gain element.
Click to expand...

Why bother? An IMPATT diode will do the oscillation (negative resistance)
just fine, and antiphase is pretty easy; at 1.5 GHz, a few inches of transmission
line is a hundred eighty phase shift. Tunnel diode type items are the bomb for
this kind of thing.
 
On Tue, 1 Feb 2022 13:53:21 -0800 (PST), whit3rd <whit3rd@gmail.com>
wrote:

On Tuesday, February 1, 2022 at 8:08:02 AM UTC-8, jla...@highlandsniptechnology.com wrote:

I was just fooling around. What I really want is a 1.5 GHz oscillator
with two antiphase outputs. A MMIC might be a good gain element.

Why bother? An IMPATT diode will do the oscillation (negative resistance)
just fine, and antiphase is pretty easy; at 1.5 GHz, a few inches of transmission
line is a hundred eighty phase shift. Tunnel diode type items are the bomb for
this kind of thing.
Click to expand...

Have you built an impatt oscillator in this frequency range? Impatts
are usually pulsed, high power at higher frequencies.

Does anybody still sell TDs?

--

If a man will begin with certainties, he shall end with doubts,
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon
 
jlarkin@highlandsniptechnology.com wrote:

> Not actually a Hartley, bacause the Ls are not coupled.

[...]

Without doubt, the worst oscillator I have ever seen anyone design. You are
right. You are not an analog guy.
 
On Wed, 2 Feb 2022 01:55:39 -0000 (UTC), Arnie Dwyer <spamme@not.com>
wrote:

jlarkin@highlandsniptechnology.com wrote:

Not actually a Hartley, bacause the Ls are not coupled.

[...]

Without doubt, the worst oscillator I have ever seen anyone design. You are
right. You are not an analog guy.
Click to expand...

What\'s wrong with it? It worked first try.

We have surface-mount inductors in stock, many values, but no tapped
inductors in that range.



--

I yam what I yam - Popeye
 
jlarkin@highlandsniptechnology.com wrote:

On Wed, 2 Feb 2022 01:55:39 -0000 (UTC), Arnie Dwyer <spamme@not.com
wrote:

jlarkin@highlandsniptechnology.com wrote:

Not actually a Hartley, bacause the Ls are not coupled.

[...]

Without doubt, the worst oscillator I have ever seen anyone design. You
are right. You are not an analog guy.

What\'s wrong with it? It worked first try.

We have surface-mount inductors in stock, many values, but no tapped
inductors in that range.
Click to expand...

You don\'t need tapped inductors. You make the feedback with tapped
capacitors. That means capacitors in series.

The problems are obvious. You tried to make a colpitts with a hartley
configuration. You ended up with parasitic oscillations and very poor
control over the oscillator amplitude. This gives unwanted sidebands in the
output and very poor phase noise.

Just for you, I looked up my old xtalosc.zip file. Start with the
readme.txt file. It is intended for colpitts oscillators but will work with
any lc oscillator. Just start with an inductor impedance of 50 ohms at your
target frequency and use a fast enough transistor or logic device.

https://tinyurl.com/2p9yrxmy
 
On Wed, 2 Feb 2022 07:23:10 -0000 (UTC), Arnie Dwyer <spamme@not.com>
wrote:

jlarkin@highlandsniptechnology.com wrote:

On Wed, 2 Feb 2022 01:55:39 -0000 (UTC), Arnie Dwyer <spamme@not.com
wrote:

jlarkin@highlandsniptechnology.com wrote:

Not actually a Hartley, bacause the Ls are not coupled.

[...]

Without doubt, the worst oscillator I have ever seen anyone design. You
are right. You are not an analog guy.

What\'s wrong with it? It worked first try.

We have surface-mount inductors in stock, many values, but no tapped
inductors in that range.

You don\'t need tapped inductors. You make the feedback with tapped
capacitors. That means capacitors in series.
Click to expand...

Sure. Colpitts has been around for about a century. This is a design
group. Instant hostility to ideas is easy.



--

I yam what I yam - Popeye
 
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