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#1
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I built the circuit from the page below.
http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. I used a 1N416E diode and a 1500pf filter capacitor. The tuning cap doesn't have any affect. Should this circuit work? If so what could I be doing wrong? Mike |
#2
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"amdx" wrote in news:4f6f2$46a49e2b$18d6b40c$11917
@KNOLOGY.NET: http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm Hi: That circuit should work. The exact value of the filter capacitor is not critical. Lead length is important. If your copy look EXACTLY like the pictures then it could work. The diode pictured is important. A common glass type diode will not work well. Also the pictured diode type is very static sensitive and should come to you wrapped in metal foil. If it wasn't likely the problem is a bad diode. Building things for this high of frequency is tricky and if any short cuts are taken it will probably stop the device from working well. John Passaneau W3JXP |
#3
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![]() "John Passaneau" wrote in message ... "amdx" wrote in news:4f6f2$46a49e2b$18d6b40c$11917 @KNOLOGY.NET: http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm Hi: That circuit should work. The exact value of the filter capacitor is not critical. Lead length is important. If your copy look EXACTLY like the pictures then it could work. The diode pictured is important. A common glass type diode will not work well. Also the pictured diode type is very static sensitive and should come to you wrapped in metal foil. If it wasn't likely the problem is a bad diode. Building things for this high of frequency is tricky and if any short cuts are taken it will probably stop the device from working well. John Passaneau W3JXP Hi John, I tried to keep leads short, I built it per the pictures and dimensions. I did use a microwave diode (1N416E) I did ruin one diode soldering #14 wire to it (I think). So I just soldered a small diameter wire to the next diode and attached the small wire to the circuit. The problem is the erratic reading near the microwave oven. Seems like the filter cap would smooth that. Mike |
#4
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On Mon, 23 Jul 2007 07:25:15 -0500, amdx wrote:
I built the circuit from the page below. http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. Don't treat the microwave oven as a "steady source" for RF. There is usually a rotating "stirrer" in the waveguide entrance to the cooking chamber. This is engineered to more evenly distribute the RF energy about the cooking chamber -- eliminating (hopefully) hot and cold spots. You may actually be seeing peaks and nulls as an artifact of this design. HTH Jonesy -- Marvin L Jones | jonz | W3DHJ | linux 38.24N 104.55W | @ config.com | Jonesy | OS/2 *** Killfiling google posts: http://jonz.net/ng.htm |
#5
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![]() "amdx" wrote in message ... I built the circuit from the page below. http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. I used a 1N416E diode and a 1500pf filter capacitor. The tuning cap doesn't have any affect. Should this circuit work? If so what could I be doing wrong? Mike Hi Mike That device looks so interesting to me that I will build one. Have you thought about the reason for using the Quad? It seems that complexity of the Quad+Reflector with the tuning capacitor might be used for some reason other than gain. A dipole over a piece of copper would be about the same "gain". And, since the output of this device never needs to connect to a coax, why do you suppose the *right angle* BNC is used? I'll learn something from this project. Jerry |
#6
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On Mon, 23 Jul 2007 17:10:00 GMT, "Jerry Martes"
wrote: "amdx" wrote in message . .. I built the circuit from the page below. http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. I used a 1N416E diode and a 1500pf filter capacitor. The tuning cap doesn't have any affect. Should this circuit work? If so what could I be doing wrong? Mike Hi Mike That device looks so interesting to me that I will build one. Have you thought about the reason for using the Quad? It seems that complexity of the Quad+Reflector with the tuning capacitor might be used for some reason other than gain. A dipole over a piece of copper would be about the same "gain". And, since the output of this device never needs to connect to a coax, why do you suppose the *right angle* BNC is used? I'll learn something from this project. Jerry Hi Jerry, You do point out a number of unnecessary elaborations. Tuning the driven element (what in the world for?) necessarily invalidates any director utility. Also, that humongous booger holding the director to the driven element has got to be a huge detuner. Imagine it scaled for a 20M Quad antenna. The design looks like buttoning your fly to your shirt to keep your pants from falling down. 73's Richard Clark, KB7QHC |
#7
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Jerry Martes wrote:
"amdx" wrote in message ... I built the circuit from the page below. http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. I used a 1N416E diode and a 1500pf filter capacitor. The tuning cap doesn't have any affect. Should this circuit work? If so what could I be doing wrong? Mike Hi Mike That device looks so interesting to me that I will build one. Have you thought about the reason for using the Quad? It seems that complexity of the Quad+Reflector with the tuning capacitor might be used for some reason other than gain. A dipole over a piece of copper would be about the same "gain". And, since the output of this device never needs to connect to a coax, why do you suppose the *right angle* BNC is used? because that packaging worked for the original builder? It stands off nicely from the BNC/Banana adapter? I once built some helical antennas and used TNC connectors I had in my junkbox. The TNC to BNC or TNC to SMA adapters I then had to use actually cost more than the whole rest of the antenna, and certainly more than a SMA chassis mount connector would have. Should have just used the right connector from the start. I'll learn something from this project. Jerry |
#8
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Richard Clark wrote:
On Mon, 23 Jul 2007 17:10:00 GMT, "Jerry Martes" wrote: "amdx" wrote in message .. . I built the circuit from the page below. http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. I used a 1N416E diode and a 1500pf filter capacitor. The tuning cap doesn't have any affect. Should this circuit work? If so what could I be doing wrong? Mike Hi Mike That device looks so interesting to me that I will build one. Have you thought about the reason for using the Quad? It seems that complexity of the Quad+Reflector with the tuning capacitor might be used for some reason other than gain. A dipole over a piece of copper would be about the same "gain". And, since the output of this device never needs to connect to a coax, why do you suppose the *right angle* BNC is used? I'll learn something from this project. Jerry Hi Jerry, You do point out a number of unnecessary elaborations. Tuning the driven element (what in the world for?) necessarily invalidates any director utility. Also, that humongous booger holding the director to the driven element has got to be a huge detuner. Imagine it scaled for a 20M Quad antenna. The design looks like buttoning your fly to your shirt to keep your pants from falling down. At least the quad is more rugged than a dipole. I've built a fair number of dipole type probes and they're always getting bent. These days, I build probes by etching/machining/razorblading on copper clad, or copper tape on a piece of insulating substrate. 73's Richard Clark, KB7QHC |
#9
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In article ,
"amdx" wrote: I built the circuit from the page below. http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. I used a 1N416E diode and a 1500pf filter capacitor. The tuning cap doesn't have any affect. Should this circuit work? If so what could I be doing wrong? Mike Hmmmm, I am not suprised at you 0V out near the Wireless Router, when compared with a Microwave Oven, the difference in Power Output IS significant. (100Mw Spread Spectrum, 100+ Watts CW) |
#10
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![]() "You" wrote in message ... In article , "amdx" wrote: I built the circuit from the page below. http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm The I get 0v out when held near my wireless router, if I put it near the microwave oven, the high input impedance meter bounces up and down between 7mv and 80mv and everything in between. I used a 1N416E diode and a 1500pf filter capacitor. The tuning cap doesn't have any affect. Should this circuit work? If so what could I be doing wrong? Mike Hmmmm, I am not suprised at you 0V out near the Wireless Router, when compared with a Microwave Oven, the difference in Power Output IS significant. (100Mw Spread Spectrum, 100+ Watts CW) Hi You It seems reasonable to assume the oven door was closed when the voltmeter readings were made. But, If-*IF* the meter readings were accurate *and* he was able to read even 1 mv at the Router and 80mv at the oven, there is alot-*alot* of error introduced into this test from somewhere. The math and power level estimates are left for the readers to deal with. Jerry |
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