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Bird RF Watt Meter Questions

Ok after looking at the links you posted (thanks) I think im leaning more towards the palstar or autek meters. They seem simpler and are much much cheaper. I dont need slugs either. Can someone explain how the cross needle meters work? I see one needle is forward power, one is reflected power. Where does SWR show on a meter like that? Also someone above suggested a meter that can read PEP. Can a cross needle meter read PEP? Is the power reading on the cross needle meter peak or average or both. Also, im guessing it is a powered meter? It dosent really say in the link.
 
There is a scale that has numerous lines on it. It starts on the reflected side and as the reflected power goes up, the needle cross over the appropriate line for the swr showing a higher swr.
 
Sniper308 said:
Ok after looking at the links you posted (thanks) I think im leaning more towards the palstar or autek meters. They seem simpler and are much much cheaper. I dont need slugs either. Can someone explain how the cross needle meters work? I see one needle is forward power, one is reflected power. Where does SWR show on a meter like that? Also someone above suggested a meter that can read PEP. Can a cross needle meter read PEP? Is the power reading on the cross needle meter peak or average or both. Also, im guessing it is a powered meter? It dosent really say in the link.
Click to expand...


One needle reads forward power and one needle reads reflected power. Where the two meters cross is where you read the SWR on a separate scale.As for whether it is avg or pep that depends on the individual meter if it has that ability. Here is the front panel of the daiwa CN-801HP like i have. See the scales? It does read true peak power.

1124.JPG
 
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I see now. I wondered how they worked. Less SWR means more forward power and vice versa. On the Archer(30yr. Old) antenna matcher I'm using on my temporary setup I adjust it for the lowest SWR on the frequency I'm on and then tweak it to get to radio's output power at the established power output level using a power meter.
 
Ok. I ordered the After WM1 meter. Hopefully that will be a good one. Now I seem to be having another problem maybe someone here can shed some light on. I'll start out by explaining my setup so please bear with me.

If I run a 3ft coax from the rear of my radio to the transmitter in side of my power meter and then hook the out side of my power meter to my 100ft coax going to my antenna, I get a 1.0:1 reading both on the face of the radio and on my astatic power/SWR meter. Everything seems good with this set up.

Ok. Then I run the same 3ft jumper from the rear of the radio this time going to the input side of my texas star dx500v, then another 3ft jumper from the output of the amp to the input of the power/swr meter and then the 100ftcoax out of the meter to my antenna. When I have the radio configured this way with the amp inline, my external meter shows a SWR of roughly 1.3:1 but the SWR meter onthe radio is going very high (6 to 10 on the radios internal swr meter) and the SWR/antenna warning light on the radio lights up.

I have been told 3 different things by 3 different people. Maybe you guys can give me your opinion. This is what I have been told.

1. The internal radio reading is not reliable. I should only pay attention to the external meter reading and ignore the SWR/antenna warning light on the radio. This person says as long as my SWR is good without the amp which it is that the amp is causing a false reading on the radio meter. I will add that while the radio is showing high swr value and the antenna warning light is flashing the external needle type swr meter never goes above 1.3:1. Swr on the external meter is always 1.0:1 and also 1.0:1 on the radios swr meter with either the amp left inline and turned off or taken completely out of the set up.

2. I have been told that there is an impedence mismatch between my radio and my amp and that I should place an antenna tuner inline to correct the mismatch or my radio will be damaged.

3. Another person (a local cb shop) told me that I should try changing some of the jumpers between the radio/amp/meter to different lengths and this would solve the high SWR on the radio. Im not so sure I believe this one.

And for a few other questions...

Is this the proper set up for reading the amps power and using the amp?
Radio ---amp input amp output----meter input meter output---antenna

Is the radio getting the high SWR values from the coax itself or is it reading stray rf out of the air for lack of a better analogy.

Would an antenna tuner solve this problem and if so could someone recomend a good one?
 
If the radio is showing a 6 to 1 VSWR with the amp inline, there is definitely a mismatch to the input of the amp. One important part of this diagnosis is determining if this VSWR is bad only when the amp is inline or if it has to be on for the bad VSWR to show?

If the VSWR is only bad when the amp is in the operate mode, the input stage to the amp is not tuned correctly. If the VSWR is bad whenever you put the amp inline and it's off, the problem in the RF wiring through the relay inside the amp. Sometimes they don't use shielded wiring here and that wrecks the 50 ohm impedance.
 
Shockwave said:
If the radio is showing a 6 to 1 VSWR with the amp inline, there is definitely a mismatch to the input of the amp. One important part of this diagnosis is determining if this VSWR is bad only when the amp is inline or if it has to be on for the bad VSWR to show?

If the VSWR is only bad when the amp is in the operate mode, the input stage to the amp is not tuned correctly. If the VSWR is bad whenever you put the amp inline and it's off, the problem in the RF wiring through the relay inside the amp. Sometimes they don't use shielded wiring here and that wrecks the 50 ohm impedance.
Click to expand...

The SWR readings are only bad on the radio meter when the amp is hooked up and TURNED ON. The amp can be left hooked up but TURNED OFF and the SWR readings will be the same on the radio and on the meter. Around 1.3:1.

If the input stage of the amp is not tuned correctly shouldnt the external SWR meter be reading high as well with the amp on? I guess im most curious why two meters are giving 2 totally different readings on the same hookup. I just dont want to damage my radio bottom line.
 

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