After peaking and tuning this radio the owner said he had a swr warning light problem with the radio. It's dk = 10w ( a little high but not for the 1969 final to handle) and swings to 22-23w. It shows the light even with just keying up with the carrier. I have seen the galaxy tech support memo about replacing c5 with a 22k resistor. This is an smt board and very difficult to work with; does anyone have a different solution to this fix. Thanks.
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galaxy 959 with swr warning light
- Thread starter Cityboy
- Start date
reduce carrier to 5.5 - 5.75W. for 100% modulation the carrier should be one fourth of the total (22-23W) modulated power output.
See: RATIO OF PEP TO CARRIER POWER FOR 100% MOD DEPTH
See: RATIO OF PEP TO CARRIER POWER FOR 100% MOD DEPTH
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excerpt from the DX959 Service Manual
17. SWR ALERT LED
This LED lights red when your SWR is higher than about 3:1. This is not an exact indicator of 3:1 SWR but it is an indication that you should check your SWR reading.
further notes:
http://www.worldwidedx.com/tech-repair/31994-swr-warning-light.html#post128384
the above also applies to the GDX959. a value of exactly 16.66 ohms provides accurate calibration of the warning indicator LED (@ 3:1) in all models equipped with a calibration control, regardless of manufacturer.
17. SWR ALERT LED
This LED lights red when your SWR is higher than about 3:1. This is not an exact indicator of 3:1 SWR but it is an indication that you should check your SWR reading.
further notes:
http://www.worldwidedx.com/tech-repair/31994-swr-warning-light.html#post128384
the above also applies to the GDX959. a value of exactly 16.66 ohms provides accurate calibration of the warning indicator LED (@ 3:1) in all models equipped with a calibration control, regardless of manufacturer.
Mackmobile I used a 50 ohm dummy load to test the radio and no warning lights came on; and the other problem is on the Galaxy 959 is an automatic swr system with no calibration system which means there is no trimmer pot to adjust to get the light to go out. That works great on the cobras and unidens. Freecell and C2 how do I build a 16.67 dummy load or 150. I get your concept but what is the easiest homebrew way for me to build one with the values you gave. Thanks.
buy carbon film resistors or you can buy differnt value terminations (dummy loads).
I would just buy a pack of 2-ohm resistors and build one. You can make any value load you want by mixing them up in parallel/series combinations.
For example, a couple of 10 ohm resistors in series would be close enough (20 ohms; SWR = 2.5:1).
I would just buy a pack of 2-ohm resistors and build one. You can make any value load you want by mixing them up in parallel/series combinations.
For example, a couple of 10 ohm resistors in series would be close enough (20 ohms; SWR = 2.5:1).
C2 thanks I know how to get the 16.67 value out of parallel or series resitors; but do they need to be a 1w or 1/2 work. Also how do the loop; I have not built my own homebrew dummy load before(I need a few directions). Can I use a coax that has a p;259 and somehow attach the resistors to it; help me- I have fallen down and can't get up.
You can add the power handling of the resistors together if they are the same value.
For example, if you use seven, 1k Ohm, 1/2 watt resistors in parallel, you will have an ~143 ohm load that can handle 3.5 watts. If they are 2 Watt resistors, then total power handling is 14 Watts.
This works when in parralel or series, again when they are the same value.
If you have an odd one, then you have to figure the power dissipated in that resistor using Ohms law.
I've been know so solder resistor networks right onto a PL259 connector. The worst that has ever happend was I overpowered one and it got hot, melted the solder and it fell apart. The rig survived!
You can put a lot of resistors together, if needed:
For example, if you use seven, 1k Ohm, 1/2 watt resistors in parallel, you will have an ~143 ohm load that can handle 3.5 watts. If they are 2 Watt resistors, then total power handling is 14 Watts.
This works when in parralel or series, again when they are the same value.
If you have an odd one, then you have to figure the power dissipated in that resistor using Ohms law.
I've been know so solder resistor networks right onto a PL259 connector. The worst that has ever happend was I overpowered one and it got hot, melted the solder and it fell apart. The rig survived!
You can put a lot of resistors together, if needed:
I would use 10 x 1.5k 2 watt resistors in parallel,which would be around 150 ohms depending on tolerance and would handle 20w. 20 x 3k 1 watt ones in parallel would give the same resistance and power handling. both will give 3:1 swr and can be used to set swr warning or calibrate a radios internal swr meter.
Like it has been said...lower the dead key...really much to high. Adjust the radio for a lower dead key and better forward swing. Reset the modulation to 100% not slamming the meter. Hopefully no one has cut the limiters. Get a good dummy load and test. If it still happens go through the antenna system. Coax, mount ,ect. What type of antenna(s) ,coax, ect. Is he running a box. Lots of questions, but info that is needed.If I can help call me 2816696309.
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