It was really driving me up a wall...

The tube I had in there was an RF parts 3-500ZG.


I remembered that I had a spare 3-500 Eimac tube sitting on the shelf, and just decided to swap tubes in an effort to eliminate the Amp...and/Or add to the odds that the problem was in the feedline/Connectors/Antenna Balun, as I had originally suspected.

Imagine my suprise when the Eimac tuned up 600 Watts no problem!

So I pulled the Eimac and re-installed the RF Parts 3-500ZG and the problem returned!

With the RF Parts tube..I could start tuning the amp, and as soon as I hit @400 Watts the Plate and Grid meters would drop!
If I backed off on Driver power to lower the output below 400 Watts the Meters would jump back up to their normal levels!

Oh Well....
I ordered a new tube from RF parts today...



My Husband called Alpha Delta today to discuss the coil melting issue, and told me that A-D has confirmed that this situation was likely caused by something called a Carona Effect on the antenna ends.

That's a new one on me.....but what really shocked me was that A-D is sending me a NEW ANTENNA FREE OF CHARGE!!!

They said that this has happened before under certain conditions, and they have made changes to the design to combat this issue!

Since my Antenna is an older version, they thought the best solution was to replace the antenna completely!

This is WAY MORE than I expected!!

I was hoping that, at best, they would let me BUY a new set of coils!

A-D has made a customer for life!

Wendy

Umm....Now where did you see me post 750 Plate??


It has been 75 since I posted my original....


I do want to thank you for your statement that I have no idea what I am talking about!

That was very mature and Constuctive ....Kudos!

BRAhhhh..VooHhhhh.

Do you treat everyone that way...or just YL's???

Whiskey Tango Foxtrot....


Anyway...I found that I have a bad Primary tube....
replaced it and everything loads properly.....

I still need to change out those Antenna Coils..

Wendy

No...I really mean once it hits @400 watts....all of a sudden it drops to Plate 50 Grid 75!!!!!!

Seriously the meters drop.....!!!!

That's what I'm trying to explain!!!!

Meters all look good....as power comes up..@400 watts..Bang something happens and I see 50 plate 75 Grid!

It's like something just gives out!

HELP!!!!!

I have phoned A-D asking to buy a new set of coils...

THe original pair melted, and I had to re-wind around a new core myself once already..so asking A-D to replace these would not be the right thing to do.

Let me tell you what I am seeing...maybe I may have trouble elsewhere as well..

Since the coils have obviously distorted and melted...I'm starting my trouble shooting there...
But here is the root of my problem...

When I tune up my Ameritron AL-80B amp...I can only get to @ 400 watts..when it all of a sudden drops load and plate readings to the bottom of the scale

Grid @50 Plate @ 75...

Everything seems fine as I tune up power...but once it tunes up to @400 watts ..the grid and plate drop right off...

Backing off brings load and plate back up!!

It seems that something is Giving out as the power climbs...

Again..since the coils have been obviously melted..I'm starting there...but I suppose the problem could also Lie in the Feadline/Connectors or the Balun at the center feedpoint of the AD-DX-ee...

This is my only antenna..so I can't test it

Everything works perfectly...and tunes well barefoot!

Hit it with more power...and something isn't happy!

Oh...and there isn't any arching in my amp that I can detect..

band is 20 Meters...easily tuned...

Thanks

Wendy

I have been using my Alpha Delta DX-EE for @ 4 years now...
While this antenna is rated up to full legal power...I have had this same issue happen twice already.

Now Normally I run my Yaesu FT-990 barefoot up to 100 watts and never have a problem...

However..I also own an Ameritron AL-80B, and whenever I use it..I usually end up damaging my antenna!

The Alpha Delta utilizes 2 coils wraped around what appears to be PVC tubing.

While Using @ 600 Watts..I have evidently heated up those coils enough to melt the PVC..as they are now obviously distorted!

THis weekend...I could not use the amp at all as any power over @200 Watts was most definately arcing and driving my tuner and Amp crazy!

This antenna fits PERFECTLY in my back yard...and I hate to scrap it...

I need to either find a way to make a coil that fills the bill but can actually handle the power, or I need to replace the antenna completely!


This will be the second time I have had to rebuild those 2 coils....so I need a better solution than varnished Copper wire wound around plastic tubes!~

Thanks!!!!

Wendy

W1DY

The Edmond Amateur Radio Society will be hosting a special event station at one of Oklahoma's Territorial Capital buildings.  Monitor 21.260 14.260 and 7.260 1400-2000z on November 10 & 17 for special event call W5G.  Certificate provided to those sending a large envelope with appropriate postage to:  EARS, PO Box 48, Edmond, OK 73083.  More information located at http://www.k5eok.org.

It seemed like a cheap insurance policy.

After seeing how hard the band switch is to get to...I decided an ounce of prevention is worth a pound of cure.

I just thought it was better to be proactive rather than put my head in the sand and Hope nothing bad happened.

Wendy

OOppps...
Forgot to put an e-mail address...for anyone that can help...

wquinn2@yahoo.com

Thanks again!
Wendy

Please HELP!!!!!!

I just bought a Low VHF-Q/Low VHF-Rp Parasitic Suppressor Retrofit-Kits from Richard L. Measures, AG6K.
 
It includes nickel-chromium-iron alloy wire; 430'F / 221'C tin-silver solder and nichrome soldering flux, glitch protection and RF-NFB resistors; capacitors; 200a-peak glitch protection diodes; instructions; diagrams and a condensed version of the Oct 1988 QST article.

Well... I thought I could install this myself....
But after looking through the kit and reading the instructions...(5 times) I'm lost....(not that good at relating the schematic to what is actually inside the amp and where)

I really need a Picture or 2 to Jog me and give me the ability to get my bearings on just how to assemble..and what goes where!

A couple of pictures of an actual install is really going to help a LOT!...

If anyone has installed this kit in an AL-80B...and could take a couple of snapshots of the install...It would be a great help!..

I have already installed Ameritron's Grid Protection board in the amp...but according to Mr. Measures, it is too slow to protect against VHF-Rp Parasitics. (It just helps keep me from making a big mistake while tuning.

If there is anyone that can guide me...I know that I can find them here on Eham.!

Wendy
W1DY

Has anybody ever purchased cards from Octavia?  It has now been three months and I have not received my cards.  My e-mails recently go unanswered when I ask where they are.  This company has even sold my e-mail address to everyone in the world.  Not cool.

I have a custom one-sided b&w card that I want to have printed.  Any suggestions?

Traps are out for me....
I need something to handle 1KW.

I guess 160 is out of the question...and really not needed to get my 5 band DXCC.

I have a G5RV...and was just thinking....
If I was to join the ends..I would have a Loop...

But it would only be 103' long....
I guess this weekend I'm going to have to measure off the entire back yard to see what the MAX total length would be...

I could feed from the mast on my house that has the DX-EE already on it...
That is as high as I can go....
Then run the corners as high as practical...

I have had ZERO luck with HomeBrews...
But every antenna I bought has worked wonders!

If this keeps up...I'm going to get an Inferiority complex!

Since I'm now concentrating on a 80 Monoband..Or a 40/ 80...
That should open up some options for me...
SO I guess the question is what is the best/Shortest 80 Meter antenna w/o traps?
What about those ISOTRON...antennas....??

Wendy

My Husband Just bought me my first amp...
An Ameritron AL-80B.

I had been running barefoot out of my Yaesu FT-990 for years.

It was a TOTAL Suprise when this Huge box arrived!

About 2 weeks later an Ameritron ATR-15 antenna tuner also found it's way to our door!

Let me tell you...it has been quite a learning experiance!..
But...If I knew then What I know now...!!

This has totally opened up a new world of DX for me!
I am completely sold on Ameritron products...But as this is my first amp..I am also COMPLETELY biased!

Sure I'd love to buy a new QRO amp....but I'd like to hit the lottery too!

All I can say is that I LOVE Mine..
I don't think you could go wrong with one as well!

Good Luck...and trust me...make the plunge..you'll never look back !

Wendy

Horizontal loop....

Now you do mean running the wire parallel to the ground correct?

How high off the ground does it need to be?

Do you have a diagram...or a link to a "How To Build" plan?

If I lay this out I can give it to my Husband to build and install when he get's his next "Honey Do" list!

W1DY

Right now, I am using an Alpha Delta DX-EE..and having a LOT of SUCCESS with it!
It is covering 10-40 no problem for me...
Although 40 doesn't tune SWR as low as I'd like even with my Ameritron ATR-15 tuner...

Anyway...

I need something for 80...160 would be nice also..but the length requirements that I've seen prohibit installing in my yard...

Length is my main concern.....I just don't have a lot to work with...

Any one leg can't be more than @60 feet... (unless it can straddle my roof.)

I looked at the Alpha Delta DX-B..but it seems useless without a yagi or the like to act as a capacitor hat.

I'm looking at the DX-A. now..but I don't want to narrow my choices yet.

Thanks
73
Wendy

I hope I didn't start a WAR here!

Right now I have An Eimac 3-500Z in there..and have a RFP 3-500 ZG on it's way....
(read higherup and see what happened to the original they sent)

Anyway...With what I have ...
I tried tuning up the amp...and what I'm seeing is that on voice peaks...with @350 lp...
I can still hit @1000-1100 watts on the output meter!

The SWR is barely moving so almost nothing back!

Normal voice @750-850 Out.

Place and Grid are WAY below MAX...

On tune up...(pulsed CW)I get @400 lp at @70-75 Watts Drive.

By all readings the ALC level seems fine.

Anyway...All I can go by are the meters I have....
I will take the advice here to heart..and watch those meter readings so as to not spatter.


I'm impressed with this amp...!

So many years running my FT-990 Barefoot!

Thanks for all the great info!
Now to get my Husband to learn CW to get his ticket...

HOLD THAT THOUGHT...If he get's his ticket..I'll never get my Mic Back!

73
Wendy