Arcing noise identified in Ranger

[wx3k]

I have noticed this arcing sound that would last for about 4 -5 seconds then stop. It sounded like it was coming from the power transformer in the rear of the rig. It would happen randomly while the transmitter was in standby. It also happens while the transmitter was transmitting. There did not seem to be any pattern to this. It doesnt happen with consistency. Over the past month, I have noted that my output power was drifitng up and down. I thought it might be time to replace the final in the ranger. I plugged a new one in and fired up the rig. Power output was improved and completely stable. Excellent. During the time I was powering the rig on and off, I noted arcing in the 5U4 rectifier. Ah, whenever the 5U4 arcs over the power transformer makes this noise. Why is the 5U4B arcing over ? I tried another 5U4B and it too arcs when powering up the rig. This is not a healthy occurrence.

[KE6DF]

I don't own a Ranger, and there are many here who are experts on them, but in looking at the Schematics for both Ranger and Ranger II they both use 5R4's as recitfiers.

Now 5R4's have higher voltage specs than 5U4's.

So the problem could be as simple as switching to a 5R4.

Now that I say this, there might be several Ranger owners who have been using 5U4's for years, so probably best to wait for one of the experts to post.

But if you have a 5R4 you might try it.

:-)

Dave

[WQ9E]

Stephanie,

As the other poster noted, the proper HV rectifier is a 5R4.  A 5U4GB is rated up to around 550 VAC on the plates and the Ranger 2 with fairly high line voltage will be up in the 800-850 range so that is likely the problem.

Also check and make sure that there is no arcing on the socket from carbon tracking, if so clean it.

The other option is to go solid state if you don't have a 5R4 available.

[KE6DF]

If you don't have a 5R4 I could send you a couple.

[wx3k]

How about that. I never noticed this. The ham I bought the rig from said it worked fine. Hmm....Very interesting.

I had ONE 5R4 from another power supply that I was fixing. Tested the 5R4, installed and it works !

Awesome...Thank you very much guys !

Stephanie,

As the other poster noted, the proper HV rectifier is a 5R4.  A 5U4GB is rated up to around 550 VAC on the plates and the Ranger 2 with fairly high line voltage will be up in the 800-850 range so that is likely the problem.

Also check and make sure that there is no arcing on the socket from carbon tracking, if so clean it.

The other option is to go solid state if you don't have a 5R4 available.