Date   

Re: Question About The 4 States Antenna Tuner

Jim, N5IB
 

BTW ... of interest to many... There is a simulator of the T network tuner at:
http://fermi.la.asu.edu/w9cf/tuner/tuner.html

It's a great way to practice adjusting the beast without smoking too many finals. Also has an optimized "autotune" function that can predict what your own tuner settings may need to be for a given load condition ( R +/- jX that the Nano VNA can tell you about). For example - it predicts that at 7 MHz the 50 ohm dummy load (50 + j0) should match with both caps at near maximum, and the inductor near minimum.

To run your computer does need to have JAVA installed, so it may not be everyone's cup of "tea"

Jim, N5IB


Re: Question About The 4 States Antenna Tuner

Jim, N5IB
 

Hi Dave,

I looks like something is working as it should... but the trouble with that test is you're still testing two things at once - the bridge part and the tuner part. You need to isolate the functions to home in on the problem.

Since you have a Nano VNA, set it at some fixed frequency, say 7050 kHz, and connect it to the tuner. Set the bridge to OUT, and connect the dummy load in place of the antenna. Adjust the L/Cs to attempt to find a 1:1 match as indicated on the Nano.

If you can make a match close to 1:1, then leave the L and C settings right where they are, disconnect the Nano and connect up your transmitter, set to the same frequency, still with the dummy load in place, but with the bridge now IN. When you key the transmitter it should see the match that you found, and the LEDs should confirm it - REV off or very dim, FWD on and bright. If that's not the case then something is amiss in the bridge part. It's possible you might need very slight adjustments to perfect the match, but only very slight.

Jim, N5IB


Re: Question About The 4 States Antenna Tuner

Dave W0DCX
 

I ran the dummy load test this morning.  Attached is a table in MS Word showing the results.  At least with the dummy load there is a semblance of functionality.  When I first tried the Tuner I had the Elecraft AX1 20-meter vertical whip antenna attached which I know has an SWR of about 1.3:1 but then I saw nothing but the RED LED illuminated which seemed wrong to me.  Totally different behavior with the dummy load attached.  I would be interested in your interpretations of this data.  Thanks.
Dave W0DCX


Re: Question About The 4 States Antenna Tuner

Jim, N5IB
 

Dave (NM0S..... get ready to chime in here... I'm going to risk violating Mark Twain's advice ("keep silent and be thought a fool, or speak and remove all doubt) ... and try to explain the workings of the 4 State Tuner's SWR bridge operation.

First, D2 steals, and rectifies, a bit of the RF drive which is filtered by C3 to provide a "positive supply voltage" that is connected via R4 (1 k) to the collector circuit of Q1 (NPN) and also the emitter circuit of Q2 (PNP) .

That positive supply voltage is also applied, via R6 (1 meg), to the base of PNP transistor Q2, thus biasing it OFF, and preventing, for the moment, the red REV LED from lighting.

But if the 47 ohm resistive bridge (R1, R2, R3) is unbalanced because an impedance other than 47 ohms resistive is presented through the tuner elements, then an RF voltage will be developed across the C4 - D1 combo. D1 is oriented so as to rectify the RF and develop a negative DC voltage across C4, which acts as the filter capacitor.

That negative voltage is applied via R5 (150 k) to the base of Q2, counteracting the positive bias voltage applied through R6. If the bridge unbalance is large enough, the negative bias will overcome the positive, and Q2 will begin to conduct, causing the red REV LED to illuminate. D3 serves to produce a "dead band" so that the REV LED can be seen to extinguish clearly when a match is accomplished.

The greater the load mismatch, thus the greater the bridge unbalance, the greater will be the negative bias applied to Q2 and the brighter will be the REV LED.

While all this is going on the base of Q1 (NPN) is looking at the collector of Q2. As Q2 is driven to conduct, its collector voltage decreases towards ground, turning OFF Q1 and dimming (or even extinguishing) the green FWD LED.

When a matched condition is achieved and the bridge is balanced, there is no negative bias on Q2, and it is turned OFF. Q2's collector voltage then rises in the positive direction, which forward biases Q1, turn it ON and lighting the green FWD LED.

OK Dave .... did that "remove all doubt" LOL

Jim, N5IB


Re: Question About The 4 States Antenna Tuner

Dave W0DCX
 

Thank you all for those great suggestions.  I feel like my electronics IQ rose a few points just by reading your posts.  I do have a dummy load and I recently acquired a NanoVNA so I will follow all of your suggestions and see what I can come up with.
Dave W0DCX


Re: Question About The 4 States Antenna Tuner

Jim, N5IB
 

Hi Dave,

First thing to do is determine if the problem is with the SWR bridge part or the tuner part. Unfortunately with this circuit you can' t test the just the bridge into a dummy load without having the tuner in-line.

Do you have an antenna analyzer or a separate SWR meter that will work at QRP power levels? If so, connect a dummy load to the ANT jack and switch the bridge OUT. Excite the tuner with your analyzer or with a QRP transmitter through your other SWR meter and see if you can tune for a match. If so, the Ls and Cs of the tuner part are OK and the problem is almost certainly with the bridge part. You could even do this with the antenna connected if you don't have a suitable dummy load.

NM0S used some cleverness in devising the bridge indicator, and I don't profess to understand it fully :^)) but that's not a new thing. It almost seems like yours is working "backwards" with the red LED showing forward power.

As someone else commented, if the LEDs light at all it's pretty sure they are installed correctly. But check that the other diodes (D1 and D2 in particular) are oriented correctly. And also double check that Q1 and Q2 didn't get swapped. Q1 should be a 2N3904 (NPN), while Q2 is a 2N3906 (PNP).

Also double check R5 and R6 ... easy to miss the color codes if the light is poor... R5 is 150 K (brown-green-yellow) while R6 is 1.5 Meg (brown-green-green) .

Keep us posted what you discover.

Jim, N5IB


Re: Congrats to K0NEB

Johnny AC0BQ
 

Thanks for the heads up Walter.

CONGRATS JOE!
Well deserved!
72, 73
Johnny ACØBQ 

On Sat, Jun 6, 2020 at 12:09 AM Walter - K5EST <walter.k5est@...> wrote:
Joe - K0NEB is a 4SQRP member and a well known kit editor for CQ magazine. 


73,

Walter Dufrain - K5EST - QRPcw
https://www.qrz.com/db/k5est
   

--
Check out the 4SQRP website at 4sqrp.com


Congrats to K0NEB

Walter - K5EST
 

Joe - K0NEB is a 4SQRP member and a well known kit editor for CQ magazine. 


73,

Walter Dufrain - K5EST - QRPcw
https://www.qrz.com/db/k5est
   


Re: Cyclone list and info?

Jess Gypin
 

Thanks!

On Jun 4, 2020, at 5:20 PM, AG1P Ron <ag1p@...> wrote:



GA Jess

Here is link to the Yahoo group. Not sure if anyone monitors it anymore. You might be better off posting your questions here.

https://groups.yahoo.com/neo/groups/cyclone40/info     

72  - Ron - AG1P

4SQRP Volunteer Webmaster

 

From: main@4SQRP.groups.io [mailto:main@4SQRP.groups.io] On Behalf Of Jess Gypin
Sent: Wednesday, June 03, 2020 7:19 PM
To: main@4SQRP.groups.io
Subject: [4SQRP] Cyclone list and info?

 

IS there still a group out there for the Cyclone kit? I have some questions that can’t be answered via the manual or the modifications that I have found for this rig. Or is there someone that is familiar with this kit to answer some questions. Help would be appreciated.

 

Jess AE0CW

 

Sent from Mail for Windows 10

 


Re: Question About The 4 States Antenna Tuner

Jeff Logullo N0̸MII
 

If the LEDs are lighting at all, then they're not installed backwards I wouldn't think.

Have you tried it with a dummy load connected to the antenna output? Might be good to start there, eliminating antenna variability while you're troubleshooting.

Jeff N0MII



On Jun 5, 2020, at 1:15 PM, Dave W0DCX <cwqrp73@...> wrote:

I recently completed a 4 States Tuner kit and gave it a try.  Sadly, it is not behaving correctly.  The red REV light come son and stays brightly lit no matter how I adjust the inductor or capacitors.  The green FWD is only weakly on when the inductor is at the higher inductance setting and then dims whenever either capacitor is adjusted.  It is off whenever the inductor is set at lower inductances.  Is it possible that the red LED was installed backwards? Anything else?
Thanks to anyone who might have some insight.
Dave W0DCX
_._,_._,_


--
Jeff N0̷MII


Question About The 4 States Antenna Tuner

Dave W0DCX
 

I recently completed a 4 States Tuner kit and gave it a try.  Sadly, it is not behaving correctly.  The red REV light come son and stays brightly lit no matter how I adjust the inductor or capacitors.  The green FWD is only weakly on when the inductor is at the higher inductance setting and then dims whenever either capacitor is adjusted.  It is off whenever the inductor is set at lower inductances.  Is it possible that the red LED was installed backwards? Anything else?
Thanks to anyone who might have some insight.
Dave W0DCX


Re: Cyclone list and info?

AG1P Ron
 

GA Jess

Here is link to the Yahoo group. Not sure if anyone monitors it anymore. You might be better off posting your questions here.

https://groups.yahoo.com/neo/groups/cyclone40/info     

72  - Ron - AG1P

4SQRP Volunteer Webmaster

 

From: main@4SQRP.groups.io [mailto:main@4SQRP.groups.io] On Behalf Of Jess Gypin
Sent: Wednesday, June 03, 2020 7:19 PM
To: main@4SQRP.groups.io
Subject: [4SQRP] Cyclone list and info?

 

IS there still a group out there for the Cyclone kit? I have some questions that can’t be answered via the manual or the modifications that I have found for this rig. Or is there someone that is familiar with this kit to answer some questions. Help would be appreciated.

 

Jess AE0CW

 

Sent from Mail for Windows 10

 


Re: For sale, built Cyclone 40

Bob - K2KI
 

Hi Ken,
Is it still available?
Please drop me a line to let me know.
Many thanks!
-- 
73/72 . .
Bob de k2ki
k2ki@...
k2ki.bb@... (Goes to my cell)
FP #4214
SKCC #12195
NAQCC #2337
On 5/23/2020 2:24 PM, Kenneth Ketner via groups.io wrote:

Still thinning the herd, will ship for $50.

Ken Ketner
KA5ELD
PO Box 65135
Lubbock, TX 79464-5135


Virus-free. www.avast.com


Re: 80 and 40 meter nets

Johnny AC0BQ
 

Thanks for calling the Net Bert.
72
Johnny ACØBQ 

On Wed, Jun 3, 2020 at 8:46 PM Robert <e1dslr@...> wrote:
Pretty Slim pickens tonight s8 s9 qrn here tonight
40 meters
WA9PWP PAUL
KL7IXI MIKE

80 METERS
HEARD A 5 STATION BUT JUST COULDN'T PULL THEM OUT OF THE NOISE
72'S
BERT
N0YJ


--
Check out the 4SQRP website at 4sqrp.com


DELTA MIKE ROMEO NET

Robert
 

THANKS TO THOSE WHO CHECKED IN
WA9BNZ BILL
WG5F ED
N0TGR DICK
KU5M JOE
K0EMT BRYAN
N0TU MIKE
KA4RUR FRED


Cyclone list and info?

Jess Gypin
 

IS there still a group out there for the Cyclone kit? I have some questions that can’t be answered via the manual or the modifications that I have found for this rig. Or is there someone that is familiar with this kit to answer some questions. Help would be appreciated.

 

Jess AE0CW

 

Sent from Mail for Windows 10

 


Re: 80 and 40 meter nets

w2sh@...
 

In NJ I could hear bits and pieces of Bert's sig on 40m.  Paul was fully readable.  Only bits and pieces of Mike's sig.  I think i did hear N4MJ.  I dropped my call sign a few times, but without any NCS acknowledgement.

On 80m I could hear sigs, but no copy whatsoever.

Charles (aka chas), W2SH


From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of Robert <e1dslr@...>
Sent: Wednesday, June 3, 2020 21:46
To: main@4sqrp.groups.io <main@4sqrp.groups.io>
Subject: [4SQRP] 80 and 40 meter nets
 
Pretty Slim pickens tonight s8 s9 qrn here tonight
40 meters
WA9PWP PAUL
KL7IXI MIKE

80 METERS
HEARD A 5 STATION BUT JUST COULDN'T PULL THEM OUT OF THE NOISE
72'S
BERT
N0YJ



--
Charles Moizeau, W2SH


80 and 40 meter nets

Robert
 

Pretty Slim pickens tonight s8 s9 qrn here tonight
40 meters
WA9PWP PAUL
KL7IXI MIKE

80 METERS
HEARD A 5 STATION BUT JUST COULDN'T PULL THEM OUT OF THE NOISE
72'S
BERT
N0YJ



Wednesday Evening 40 and 80 meter Nets - Wed, 06/03/2020 #cal-notice

main@4SQRP.groups.io Calendar <noreply@...>
 

Wednesday Evening 40 and 80 meter Nets

When:
Wednesday, 3 June 2020
20:00 to 21:00
(GMT-05:00) America/Chicago

Where:
40 and 80 Meters

Organizer:
jomatlock@...

Description:
The 40 Meter Net will be at 8:00 pm central time  on 7.122 +-. QRM
NCS is WQ5RP/ACØBQ 

Wednesday evening 80 Meter CW Net. will be at  (8:30PM Central Time Wednesday). 



The 80 meter net will be called on 3.564 MHz +/- QRM.
Net control operator is Johnny ACØBQ 

* NEW *  Wednesday evening DMR Voice Net will be at (Thursday) 0300 UTC (9:00PM Central Time Wednesday/)
Four States QRP has a Brandmeister DMR Talk Group (TG31654). Join us to discuss QRP, ask questions, or just ragchew. The Wednesday net is a directed net  but any other time you may use the Talk Group to chat with other QRPers.
Net Control operator is Bert NØYJ.


Re: Upcoming Event: Wednesday Evening 40 and 80 meter Nets - Wed, 06/03/2020 20:00-21:00 #cal-reminder

Johnny AC0BQ
 

Good afternoon Group
I have to attend my monthly Civic obligation.
Bert, N0YJ has offered to Call the 40 and 80 meter Nets tonight.
Have fun, good luck!
72
Johnny ACØBQ 

On Wed, Jun 3, 2020 at 3:00 PM main@4SQRP.groups.io Calendar <main@4sqrp.groups.io> wrote:

Reminder: Wednesday Evening 40 and 80 meter Nets

When: Wednesday, 3 June 2020, 20:00 to 21:00, (GMT-05:00) America/Chicago

Where:40 and 80 Meters

View Event

Organizer: jomatlock@...

Description: The 40 Meter Net will be at 8:00 pm central time  on 7.122 +-. QRM
NCS is WQ5RP/ACØBQ 

Wednesday evening 80 Meter CW Net. will be at  (8:30PM Central Time Wednesday). 



The 80 meter net will be called on 3.564 MHz +/- QRM.
Net control operator is Johnny ACØBQ 

* NEW *  Wednesday evening DMR Voice Net will be at (Thursday) 0300 UTC (9:00PM Central Time Wednesday/)
Four States QRP has a Brandmeister DMR Talk Group (TG31654). Join us to discuss QRP, ask questions, or just ragchew. The Wednesday net is a directed net  but any other time you may use the Talk Group to chat with other QRPers.
Net Control operator is Bert NØYJ.

--
Check out the 4SQRP website at 4sqrp.com

2981 - 3000 of 25075