Galaxy 55 HP dead key issue

[Charlie Brown]

I have it set to dead key 1 watt and swing out about 40 pep but when I just hold a dead key after speaking into the radio it takes a couple seconds for the tx to fall back to 1 watt? It usually hangs around 6 watts and then starts falling back to 1 watt where I have it set?? Whats up with that?

 

[9C1Driver]

Many of the newer mosfet powered radio's suffer from this until they warm up or you carry on a steady conversation. If that's a higher powered radio maybe it just does not like being dialed down that low.

 

[Robb]

Might have an oscillation/feedback problem.
Listen to that radio TX on another radio.

11 more points here. At 1w DK; the radio should output no more than 10w PEP, as it is a MOSFET. Getting 40w PEP output is very close the fail point for that device. Use a real 50 ohm/100w dummy load if you are going to test it at all . . .

 

[loosecannon]

yep, your radio is going into oscillations.

the main reasons for this are:

1. high antenna SWR

2. mistuned transmitter

3. power supply insufficient (radio starving for current)

the first two reasons are pretty straightforward, but the last one may sound confusing if you havent run into it before.

in the most basic sense, what is happening is that your radio is putting out the 40 watts (for example) which is the max peak amperage your power supply can deliver.
however, the power supply can only deliver that amount of current for a split second, and then it drops off.
when the current drops off, but the radio hasnt been switched back to RX mode, the TX section goes crazy and start oscillating due to the flywheel effect.

turn your mic gain down until the radio is only peaking about 15 watts or so, and see if its still having the problem.

if it is, see reasons 1 and 2.

if not, reason 3 is your culprit.
LC

 

[Charlie Brown]

PS is good. SWR is even better. idk man its steady talkn 25-30 watts. seeing the meter bump 40 if i want it to but idt its that far off.. could it be the voltage regulator?

 

[222DBFL]

What does moving the dead key up to 4 watts? Does the issue still occur? Or does it go away? May need to adjust the rf powe for 2 watts low. May help may not. A dummy load is going to help as well vs transmitting over your antenna. I would use a dummy load and check the radio, slowly turn up the rf power and see at what watt dead key the issue goes away. Like said above you want to meet a 1:4 ratio, so if your pep is 40 watts, your dead key should be around 10 watts. 4-10 watts should work fine. I know my old 55dx, the variable power goes from about 1.5 watts to around 6 watts max. This is a single final radio and has a 1969 final in it if believe. It's been a while since I have had the lid off of it. It's packed up and in the closet as I don't do AM much anymore. I would use a dummy load for testing though and not your antenna. This way you are getting the most accurate reading. That and use a decent meter. Which I am sure you already know . Haven't owned any of the new MOSFET galaxy radios. The old ones are great AM radios and have good audio as well. I bought it as I like the old galaxy radios and used to run one on AM with power. Had a bleeder station back then, a 2 pill with driver, running an 8 pill. I used a galaxy 33 and an old norrhstar 3300 or something like that, basically same radio as the galaxy 33. Anyway, it might be the regulator, have you checked that the regulator isn't getting hot? Hole you get it resolved and keep us posted. God bless.