From bradk4rt at gmail.com  Sun Dec  3 12:27:44 2023
From: bradk4rt at gmail.com (B Farrell)
Date: Sun, 3 Dec 2023 12:27:44 -0500
Subject: [AMRadio] Question for GK500 owners
Message-ID: <CAHzr7C84dG3yfHD=CREjcAQDXM5Z5ApgRYjxYUUAX8qBmMcPmw@mail.gmail.com>

I'm having trouble with my Globe King 500B, which previously functioned
properly.

Now, the initial tune up process is per the manual, and with the exciter
set to VFO Operate and closing the Transmit switch, the plate current dips
to around 160 mA adjusting the Final Plate Tuning cap. But advancing the
Ant. Loading cap I'm unable to increase plate current more than a few
milliamps, and regardless how much Ant. Loading is advance the current is
well under 200 mA and RF output is a little over 100 watts. This occurs on
80 and 40 meters. On 20 meters, when I close the Transmit switch, I can dip
plate current to 200 mA but it cannot be increased above that. I have not
tried other bands. Switching the fixed Ant. Coupling caps has little impact
on the plate current for each band I've tested. There seems to be
sufficient drive.

I have swapped the 6146 drive tube and the 4-250 final tube with no change.
I have checked the resistors and fixed caps associated with the drive and
final tubes, and plate voltages at the drive and final tubes is close to
what WRL specified. As far as I can determine, the switches and relays are
functioning properly. I have tightened every ground point I can see and the
tube socket connections appear intact. I reheated a few solder connections
that looked as if they needed it.

Have you experienced anything like this with your GK500? Were you able to
determine the cause?

73,
Brad K4RT

From w5jo at brightok.net  Sun Dec  3 15:37:01 2023
From: w5jo at brightok.net (w5jo at brightok.net)
Date: Sun, 3 Dec 2023 14:37:01 -0600
Subject: [AMRadio] Question for GK500 owners
In-Reply-To: <CAHzr7C84dG3yfHD=CREjcAQDXM5Z5ApgRYjxYUUAX8qBmMcPmw@mail.gmail.com>
References: <CAHzr7C84dG3yfHD=CREjcAQDXM5Z5ApgRYjxYUUAX8qBmMcPmw@mail.gmail.com>
Message-ID: <F1DD9A8CB49E43A1B1208AA7B725AF12@JimPC>

Do you have an MFJ 259B?  If so feed it into the antenna port, be sure the 
antenna relay is closed and put a 2500 to 3 K (preferably 2.8K) carbon 
resistor from the plate of the 4-250 to ground.    Set the frequency of the 
259 to an 80 meter frequency of interest then try tuning the final to see if 
you can match to around 50 ohms on the 259.  Of course, be sure the final 
band switch is set to 80 meters.

If you can tune the meter to see a ~50 ohms on the 259 then the final 
compartment is ok.  If not you have problems in it.    It almost sounds as 
if you are tuning a harmonic rather than the fundamental.  Have you tried 
replacing the final tube?  I hope you are trying to load into a dummy load, 
if not, the antenna is wrong, maybe.  Are all connections in the final 
compartment good, nothing has come loose?

I don't need to remind you to do this with all voltages turned off, but will 
anyway.

Jim
W5JO


-----Original Message----- 


I'm having trouble with my Globe King 500B, which previously functioned
properly.

Now, the initial tune up process is per the manual, and with the exciter
set to VFO Operate and closing the Transmit switch, the plate current dips
to around 160 mA adjusting the Final Plate Tuning cap. But advancing the
Ant. Loading cap I'm unable to increase plate current more than a few
milliamps, and regardless how much Ant. Loading is advance the current is
well under 200 mA and RF output is a little over 100 watts. This occurs on
80 and 40 meters. On 20 meters, when I close the Transmit switch, I can dip
plate current to 200 mA but it cannot be increased above that. 73,
Brad K4RT


From lexnonscripta at usa.com  Mon Dec  4 12:27:00 2023
From: lexnonscripta at usa.com (Mark)
Date: Mon, 4 Dec 2023 11:27:00 -0600
Subject: [AMRadio] HRO 50 T
In-Reply-To: <F1DD9A8CB49E43A1B1208AA7B725AF12@JimPC>
References: <CAHzr7C84dG3yfHD=CREjcAQDXM5Z5ApgRYjxYUUAX8qBmMcPmw@mail.gmail.com>
	<F1DD9A8CB49E43A1B1208AA7B725AF12@JimPC>
Message-ID: <91153dc5-95f8-48a4-b249-7754e778c5ad@usa.com>

Hello, All!

I realize this is probably a stretch, but my nice HRO 50 has had a
missing bottom cover. Don't know what happened to it, as thats how I got
it. It was so nice looking I just had to get it, in spite of that. Any
of you fine gentlemen know if there is one around that I might be able
to aquire - or someone to contact about the possibility?

73,
De KD9cxh
Mark


--
This email has been checked for viruses by Avast antivirus software.
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From lexnonscripta at usa.com  Fri Dec  8 06:47:13 2023
From: lexnonscripta at usa.com (Mark)
Date: Fri, 8 Dec 2023 05:47:13 -0600
Subject: [AMRadio] HRO 50 T
In-Reply-To: <91153dc5-95f8-48a4-b249-7754e778c5ad@usa.com>
References: <CAHzr7C84dG3yfHD=CREjcAQDXM5Z5ApgRYjxYUUAX8qBmMcPmw@mail.gmail.com>
	<F1DD9A8CB49E43A1B1208AA7B725AF12@JimPC>
	<91153dc5-95f8-48a4-b249-7754e778c5ad@usa.com>
Message-ID: <22379faf-6dc0-4def-8f82-bb44ab04e2aa@usa.com>

I have received a couple of responses to my request from Jeff WA4AW -
but he isnt getting my responses.

Jeff, can you check your spam folder? I have responded to every email,
but it looks like you arent getting them for some reason.

Apolgies to the List for having to send Jeff a message here.

Thanks,

Mark KD9CXH




On 12/4/2023 11:27 AM, Mark wrote:
> Hello, All!
>
> I realize this is probably a stretch, but my nice HRO 50 has had a
> missing bottom cover. Don't know what happened to it, as thats how I got
> it. It was so nice looking I just had to get it, in spite of that. Any
> of you fine gentlemen know if there is one around that I might be able
> to aquire - or someone to contact about the possibility?
>
> 73,
> De KD9cxh
> Mark
>
>
> --
> This email has been checked for viruses by Avast antivirus software.
> www.avast.com
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