The diode in this amp on the filter cap board shorted. That caused the grid
and plate current meters to read the same. Just the plate current divided on
the two meters.
Jim W7RY
--------------------------------------------------
From: "Ron Spencer" <n4vos@bellsouth.net>
Sent: Thursday, December 23, 2010 5:36 PM
To: <amps@contesting.com>
Subject: Re: [Amps] Amps Digest, Vol 96, Issue 48
> Re AL-1500 Plate Meter Circuit
>
> Might want to check a diode on the filter cap board its a 1n4007 I had a
> meter problem on a AL-1200 and the diode was open causing it to have
> higher
> readings that normal
>
> Ron
>
> ----- Original Message -----
> From: <amps-request@contesting.com>
> To: <amps@contesting.com>
> Sent: Thursday, December 23, 2010 7:20 PM
> Subject: Amps Digest, Vol 96, Issue 48
>
>
>> Send Amps mailing list submissions to
>> amps@contesting.com
>>
>> To subscribe or unsubscribe via the World Wide Web, visit
>> http://lists.contesting.com/mailman/listinfo/amps
>> or, via email, send a message with subject or body 'help' to
>> amps-request@contesting.com
>>
>> You can reach the person managing the list at
>> amps-owner@contesting.com
>>
>> When replying, please edit your Subject line so it is more specific
>> than "Re: Contents of Amps digest..."
>>
>>
>> Today's Topics:
>>
>> 1. Re: TenTec Centurion - 422 tuning question (Lee Buller)
>> 2. AL-1500 Plate Meter Circuit (Jim W7RY)
>> 3. Re: AL-1500 Plate Meter Circuit (Jim W7RY)
>> 4. Re: AL-1500 Plate Meter Circuit (Dave Hachadorian)
>> 5. Re: AL-1500 Plate Meter Circuit (Gudguyham@aol.com)
>> 6. Re: TenTec Centurion - 422 tuning question (Gudguyham@aol.com)
>> 7. Re: TenTec Centurion - 422 tuning question (Alek Petkovic)
>> 8. Re: TenTec Centurion - 422 tuning question (Gudguyham@aol.com)
>> 9. Re: TenTec Centurion - 422 tuning question (Jim Brown)
>> 10. Re: AL-1500 Plate Meter Circuit (Jim W7RY)
>>
>>
>> ----------------------------------------------------------------------
>>
>> Message: 1
>> Date: Thu, 23 Dec 2010 12:11:45 -0800 (PST)
>> From: Lee Buller <k0wa@swbell.net>
>> Subject: Re: [Amps] TenTec Centurion - 422 tuning question
>> To: bemeier <bemeier@bellsouth.net>, amps@contesting.com
>> Message-ID: <525103.1408.qm@web81303.mail.mud.yahoo.com>
>> Content-Type: text/plain; charset=us-ascii
>>
>> Hi Lee,
>>
>> My first resuorce was to Ten Tec. They stated exactly what I thought
>> they
>> would. The amps have been in production for years and they work fine.
>> Must
>> be a problem with mine. If I want them to look at it - ship it to
>> Tennessee.
>>
>> That may be the end result, but not my desired solution.
>>
>> 73,Bruce
>>
>>
>> Well, isn't that great customer service. NOT! I am not sure that I
>> would
>> run a
>> company like that. Well, then I would assume that something is "broke"
>> or
>> out
>> of spec somewhere. As people have been writing here, seems that there
>> are
>> some
>> components to check to see if they are defective or out of tolerance(?).
>>
>> I am sure that there is a solution....after all...it is a "simple" pi-net
>> and
>> should work.
>>
>> Lee - K0WA
>>
>>
>> In our day and age it seems that Common Sense is in short supply. If you
>> don't
>> have any Common Sense - get some Common Sense and use it. If you can't
>> find any
>> Common Sense, ask for help from somebody who has some Common Sense. Is
>> Common
>> Sense divine?
>>
>> Common Sense is the image of the Creator expressing revealed truth in my
>> mind.
>> - John W. (Kansas)
>>
>>
>>>
>>
>> ------------------------------
>>
>> Message: 2
>> Date: Thu, 23 Dec 2010 13:04:59 -0800
>> From: "Jim W7RY" <w7ry@inbox.com>
>> Subject: [Amps] AL-1500 Plate Meter Circuit
>> To: "AMPS" <amps@contesting.com>
>> Message-ID: <C50FFB079339432D8FEA24CB21EE65E6@Laptop>
>> Content-Type: text/plain; charset="iso-8859-1"
>>
>> Merry Christmas!
>> I'm working on a AL-1500. I noticed that the is only one 1.5 Ohm resistor
>> in the plate metering circuit. The schematic calls for two 1.5 Ohm
>> resistors (R3 and R4).
>>
>> The plate current seems just a bit high. With 1500 watts out, plate
>> current is about 975 ma @ 2900 volts. I really believe the amp is a bit
>> more efficient than this.
>>
>> Ideas?
>> Thanks
>> 73
>> Jim W7RY
>>
>>
>> ------------------------------
>>
>> Message: 3
>> Date: Thu, 23 Dec 2010 13:07:08 -0800
>> From: "Jim W7RY" <w7ry@inbox.com>
>> Subject: Re: [Amps] AL-1500 Plate Meter Circuit
>> To: "Jim W7RY" <w7ry@inbox.com>, "AMPS" <amps@contesting.com>
>> Message-ID: <5C9B28A4CA6341C3BFD21AAF2311EB80@Laptop>
>> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>> reply-type=original
>>
>> Looking a little closer at the schematic, R3 and R4 are grid meter
>> resistors. The grid current is very low about 50 ma for 1500 watts out.
>>
>> Thanks
>> 73
>> Jim W7RY
>>
>>
>>
>> --------------------------------------------------
>> From: "Jim W7RY" <w7ry@inbox.com>
>> Sent: Thursday, December 23, 2010 1:04 PM
>> To: "AMPS" <amps@contesting.com>
>> Subject: [Amps] AL-1500 Plate Meter Circuit
>>
>>> Merry Christmas!
>>> I'm working on a AL-1500. I noticed that the is only one 1.5 Ohm
>>> resistor
>>> in the plate metering circuit. The schematic calls for two 1.5 Ohm
>>> resistors (R3 and R4).
>>>
>>> The plate current seems just a bit high. With 1500 watts out, plate
>>> current is about 975 ma @ 2900 volts. I really believe the amp is a bit
>>> more efficient than this.
>>>
>>> Ideas?
>>> Thanks
>>> 73
>>> Jim W7RY
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>
>>>
>>> -----
>>> No virus found in this message.
>>> Checked by AVG - www.avg.com
>>> Version: 10.0.1170 / Virus Database: 1435/3333 - Release Date: 12/23/10
>>>
>>
>>
>> ------------------------------
>>
>> Message: 4
>> Date: Thu, 23 Dec 2010 14:24:24 -0700
>> From: "Dave Hachadorian" <k6ll@arrl.net>
>> Subject: Re: [Amps] AL-1500 Plate Meter Circuit
>> To: "Jim W7RY" <w7ry@inbox.com>, <amps@contesting.com>
>> Message-ID: <E9F73FDCDD844374891591C8185F140C@Acer>
>> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>> reply-type=original
>>
>> Page 9 of the instructions says, "The final grid current should
>> be around 50 mA and the plate current below 1000 mA."
>>
>> By the way, the power output meter in the AL-1500 is not a real
>> wattmeter, and can be quite inaccurate.
>>
>>
>> Dave Hachadorian, K6LL
>> Yuma, AZ
>>
>>
>>
>> -----Original Message-----
>> From: Jim W7RY
>> Sent: Thursday, December 23, 2010 2:07 PM
>> To: Jim W7RY ; AMPS
>> Subject: Re: [Amps] AL-1500 Plate Meter Circuit
>>
>> Looking a little closer at the schematic, R3 and R4 are grid
>> meter
>> resistors. The grid current is very low about 50 ma for 1500
>> watts out.
>>
>> Thanks
>> 73
>> Jim W7RY
>>
>>
>>
>> --------------------------------------------------
>> From: "Jim W7RY" <w7ry@inbox.com>
>> Sent: Thursday, December 23, 2010 1:04 PM
>> To: "AMPS" <amps@contesting.com>
>> Subject: [Amps] AL-1500 Plate Meter Circuit
>>
>>> Merry Christmas!
>>> I'm working on a AL-1500. I noticed that the is only one 1.5
>>> Ohm resistor
>>> in the plate metering circuit. The schematic calls for two 1.5
>>> Ohm
>>> resistors (R3 and R4).
>>>
>>> The plate current seems just a bit high. With 1500 watts out,
>>> plate
>>> current is about 975 ma @ 2900 volts. I really believe the amp
>>> is a bit
>>> more efficient than this.
>>>
>>> Ideas?
>>> Thanks
>>> 73
>>> Jim W7RY
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>
>>>
>>> -----
>>> No virus found in this message.
>>> Checked by AVG - www.avg.com
>>> Version: 10.0.1170 / Virus Database: 1435/3333 - Release Date:
>>> 12/23/10
>>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>>
>>
>> ------------------------------
>>
>> Message: 5
>> Date: Thu, 23 Dec 2010 17:44:42 -0500 (EST)
>> From: Gudguyham@aol.com
>> Subject: Re: [Amps] AL-1500 Plate Meter Circuit
>> To: w7ry@inbox.com, amps@contesting.com
>> Message-ID: <6158c.28fa2cc.3a452ad9@aol.com>
>> Content-Type: text/plain; charset="US-ASCII"
>>
>> The AL-1500 uses the same metering board as the 1200 and 82, they both
>> use
>> 2 resistors because the full scale is 400ma on the grid. The AL-1500 has
>> a
>> 200ma FS so hence the one resistor. Your amp is correct. The AL-1500
>> usually runs about 20ma grid at 1500 out if the tube is real good. As
>> the
>> tube gets older it draws more grid current. Sounds like your OK. The
>> output
>> meter is very inaccurate, don't go by it. Lou
>>
>>
>> In a message dated 12/23/2010 4:05:15 P.M. Eastern Standard Time,
>> w7ry@inbox.com writes:
>>
>> Merry Christmas!
>> I'm working on a AL-1500. I noticed that the is only one 1.5 Ohm
>> resistor
>> in the plate metering circuit. The schematic calls for two 1.5 Ohm
>> resistors (R3 and R4).
>>
>> The plate current seems just a bit high. With 1500 watts out, plate
>> current is about 975 ma @ 2900 volts. I really believe the amp is a bit
>> more
>> efficient than this.
>>
>> Ideas?
>> Thanks
>> 73
>> Jim W7RY
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>>
>>
>> ------------------------------
>>
>> Message: 6
>> Date: Thu, 23 Dec 2010 17:46:38 -0500 (EST)
>> From: Gudguyham@aol.com
>> Subject: Re: [Amps] TenTec Centurion - 422 tuning question
>> To: k0wa@swbell.net, bemeier@bellsouth.net, amps@contesting.com
>> Message-ID: <61730.13001f6.3a452b4e@aol.com>
>> Content-Type: text/plain; charset="US-ASCII"
>>
>> I am still confused about 10 being full capacity. The dial could have
>> been put on wrong.
>>
>>
>> In a message dated 12/23/2010 3:12:03 P.M. Eastern Standard Time,
>> k0wa@swbell.net writes:
>>
>> Hi Lee,
>>
>> My first resuorce was to Ten Tec. They stated exactly what I thought
>> they
>> would. The amps have been in production for years and they work fine.
>> Must
>> be a problem with mine. If I want them to look at it - ship it to
>> Tennessee.
>>
>> That may be the end result, but not my desired solution.
>>
>> 73,Bruce
>>
>>
>> Well, isn't that great customer service. NOT! I am not sure that I
>> would
>> run a
>> company like that. Well, then I would assume that something is "broke"
>> or
>> out
>> of spec somewhere. As people have been writing here, seems that there
>> are
>> some
>> components to check to see if they are defective or out of tolerance(?).
>>
>> I am sure that there is a solution....after all...it is a "simple"
>> pi-net
>> and
>> should work.
>>
>> Lee - K0WA
>>
>>
>> In our day and age it seems that Common Sense is in short supply. If
>> you
>> don't
>> have any Common Sense - get some Common Sense and use it. If you can't
>> find any
>> Common Sense, ask for help from somebody who has some Common Sense. Is
>> Common
>> Sense divine?
>>
>> Common Sense is the image of the Creator expressing revealed truth in my
>> mind.
>> - John W. (Kansas)
>>
>>
>>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>>
>>
>> ------------------------------
>>
>> Message: 7
>> Date: Fri, 24 Dec 2010 06:53:24 +0800
>> From: Alek Petkovic <vk6apk@bigpond.com>
>> Subject: Re: [Amps] TenTec Centurion - 422 tuning question
>> To: amps@contesting.com
>> Message-ID:
>> <20101223225326.IUCN25056.nskntotgx01p.mx.bigpond.com@MARMION.bigpond.com>
>>
>> Content-Type: text/plain; charset="us-ascii"; format=flowed
>>
>> Confusing indeed. I noticed the same thing with the Emtron DX-2SP at
>> my club. Turning the knob to the right increases capacitance.
>>
>> I guess it doesn't really matter a great deal. It is just unconventional.
>>
>> 73, Alek
>> VK6APK
>>
>>
>> At 06:46 AM 24/12/2010, Gudguyham@aol.com wrote:
>>>I am still confused about 10 being full capacity. The dial could have
>>>been put on wrong.
>>>
>>>
>>>In a message dated 12/23/2010 3:12:03 P.M. Eastern Standard Time,
>>>k0wa@swbell.net writes:
>>>
>>>Hi Lee,
>>>
>>>My first resuorce was to Ten Tec. They stated exactly what I thought
>>>they
>>>would. The amps have been in production for years and they work fine.
>>>Must
>>>be a problem with mine. If I want them to look at it - ship it to
>>>Tennessee.
>>>
>>>That may be the end result, but not my desired solution.
>>>
>>>73,Bruce
>>>
>>>
>>>Well, isn't that great customer service. NOT! I am not sure that I
>>>would
>>>run a
>>>company like that. Well, then I would assume that something is "broke"
>>>or
>>>out
>>>of spec somewhere. As people have been writing here, seems that there
>>>are
>>> some
>>>components to check to see if they are defective or out of tolerance(?).
>>>
>>>I am sure that there is a solution....after all...it is a "simple"
>>>pi-net
>>>and
>>>should work.
>>>
>>>Lee - K0WA
>>>
>>>
>>>In our day and age it seems that Common Sense is in short supply. If
>>>you
>>>don't
>>>have any Common Sense - get some Common Sense and use it. If you can't
>>>find any
>>>Common Sense, ask for help from somebody who has some Common Sense. Is
>>>Common
>>>Sense divine?
>>>
>>>Common Sense is the image of the Creator expressing revealed truth in my
>>>mind.
>>>- John W. (Kansas)
>>>
>>>
>>> >
>>>_______________________________________________
>>>Amps mailing list
>>>Amps@contesting.com
>>>http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>_______________________________________________
>>>Amps mailing list
>>>Amps@contesting.com
>>>http://lists.contesting.com/mailman/listinfo/amps
>>
>>
>> http://www.qrz.com/db/vk6apk
>> http://www.qrz.com/db/vk6ap
>>
>>
>>
>>
>> ------------------------------
>>
>> Message: 8
>> Date: Thu, 23 Dec 2010 17:55:30 -0500 (EST)
>> From: Gudguyham@aol.com
>> Subject: Re: [Amps] TenTec Centurion - 422 tuning question
>> To: vk6apk@bigpond.com, amps@contesting.com
>> Message-ID: <61e34.30021b62.3a452d62@aol.com>
>> Content-Type: text/plain; charset="US-ASCII"
>>
>>
>>
>> In a message dated 12/23/2010 5:53:47 P.M. Eastern Standard Time,
>> vk6apk@bigpond.com writes:
>>
>> I guess it doesn't really matter a great deal. It is just
>> unconventional.
>>
>> 73, Alek
>>
>> It matters if the dial is on wrong and you go by the manual for initial
>> settings. NO?
>>
>>
>>
>>
>> ------------------------------
>>
>> Message: 9
>> Date: Thu, 23 Dec 2010 15:29:08 -0800
>> From: Jim Brown <jim@audiosystemsgroup.com>
>> Subject: Re: [Amps] TenTec Centurion - 422 tuning question
>> To: amps@contesting.com
>> Message-ID: <4D13DB44.1080206@audiosystemsgroup.com>
>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>
>> On 12/23/2010 2:53 PM, Alek Petkovic wrote:
>>> Confusing indeed. I noticed the same thing with the Emtron DX-2SP at
>>> my club. Turning the knob to the right increases capacitance.
>>
>> This seems to be the way Ten Tec power amps are set up. My Titans,
>> vintage 1980, are also set up that way.
>>
>> n 12/23/2010 2:46 PM, Gudguyham@aol.com wrote:
>>> I am still confused about 10 being full capacity. The dial could have
>>> been put on wrong.
>>
>> So take the cover off and look at it! That's what I did. End of
>> confusion. :)
>>
>> It's also quite easy to change, simply by taking the knob off and
>> re-seating to zero at max capacity. Now capacitance will be minimum at
>> 10.
>>
>> It's also important to realize that a pi-network is an impedance
>> matching network. So changing the value of the capacitors changes the
>> match between the output impedance of the tubes and the connected
>> transmission line.
>>
>> 73, Jim K9YC
>>
>>
>> ------------------------------
>>
>> Message: 10
>> Date: Thu, 23 Dec 2010 16:20:32 -0800
>> From: "Jim W7RY" <w7ry@inbox.com>
>> Subject: Re: [Amps] AL-1500 Plate Meter Circuit
>> To: "Dave Hachadorian" <k6ll@arrl.net>, <amps@contesting.com>
>> Message-ID: <603F5381531F4A238A95D758CCBC6EC2@Laptop>
>> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>> reply-type=response
>>
>> I know about the wattmeter Dave. I'm using a Powermaster.
>>
>> I actually answered my own question. The grid current being half of what
>> it
>> shows on the meter. So with my setup, the grid current is actually only
>> about 25 ma which is about right.
>>
>> Thanks
>> 73
>> Merry Christmas!
>> Jim W7RY
>>
>>
>>
>> --------------------------------------------------
>> From: "Dave Hachadorian" <k6ll@arrl.net>
>> Sent: Thursday, December 23, 2010 1:24 PM
>> To: "Jim W7RY" <w7ry@inbox.com>; <amps@contesting.com>
>> Subject: Re: [Amps] AL-1500 Plate Meter Circuit
>>
>>> Page 9 of the instructions says, "The final grid current should be
>>> around
>>> 50 mA and the plate current below 1000 mA."
>>>
>>> By the way, the power output meter in the AL-1500 is not a real
>>> wattmeter,
>>> and can be quite inaccurate.
>>>
>>>
>>> Dave Hachadorian, K6LL
>>> Yuma, AZ
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: Jim W7RY
>>> Sent: Thursday, December 23, 2010 2:07 PM
>>> To: Jim W7RY ; AMPS
>>> Subject: Re: [Amps] AL-1500 Plate Meter Circuit
>>>
>>> Looking a little closer at the schematic, R3 and R4 are grid meter
>>> resistors. The grid current is very low about 50 ma for 1500 watts out.
>>>
>>> Thanks
>>> 73
>>> Jim W7RY
>>>
>>>
>>>
>>> --------------------------------------------------
>>> From: "Jim W7RY" <w7ry@inbox.com>
>>> Sent: Thursday, December 23, 2010 1:04 PM
>>> To: "AMPS" <amps@contesting.com>
>>> Subject: [Amps] AL-1500 Plate Meter Circuit
>>>
>>>> Merry Christmas!
>>>> I'm working on a AL-1500. I noticed that the is only one 1.5 Ohm
>>>> resistor
>>>> in the plate metering circuit. The schematic calls for two 1.5 Ohm
>>>> resistors (R3 and R4).
>>>>
>>>> The plate current seems just a bit high. With 1500 watts out, plate
>>>> current is about 975 ma @ 2900 volts. I really believe the amp is a bit
>>>> more efficient than this.
>>>>
>>>> Ideas?
>>>> Thanks
>>>> 73
>>>> Jim W7RY
>>>> _______________________________________________
>>>> Amps mailing list
>>>> Amps@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/amps
>>>>
>>>>
>>>>
>>>> -----
>>>> No virus found in this message.
>>>> Checked by AVG - www.avg.com
>>>> Version: 10.0.1170 / Virus Database: 1435/3333 - Release Date: 12/23/10
>>>>
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>
>>>
>>> -----
>>> No virus found in this message.
>>> Checked by AVG - www.avg.com
>>> Version: 10.0.1170 / Virus Database: 1435/3333 - Release Date: 12/23/10
>>>
>>
>>
>> ------------------------------
>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>>
>> End of Amps Digest, Vol 96, Issue 48
>> ************************************
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1170 / Virus Database: 1435/3334 - Release Date: 12/23/10
>
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