take a 220v line measurement twice a day for a week and record at peak
demand and low demand periods...look at max and min...may surprise
you..definitely do not want to go high on the filament voltage for the price
of a 3-1000 and avail...is your plate trans. tapped es will your amp hv
design handle a higher plate voltage?
also may want to consider inrush current protection on the 3-1000z
filament...well worth the time es few parts..hi pwr glass envelope RF tube
production will end in 5-10 years even in China es Russia...then we will be
picking thru the dumpsters behind old broadcast stations
Cliff N7HIY
----- Original Message -----
From: "R.Measures" <r@somis.org>
To: <garyschafer@comcast.net>
Cc: <amps@contesting.com>; <dajs@accnorwalk.com>
Sent: Sunday, February 20, 2005 2:12 AM
Subject: Re: [Amps] 3-1000Z Filament Voltage Question
> Possibly, but 7.08v is definitely low for a 7.5v filament.
>
> On Feb 19, 2005, at 11:14 AM, Gary Schafer wrote:
>
>> Your meter calibration is probably off that far unless you have a very
>> good one.
>>
>> 73
>> Gary K4FMX
>>
>> Dennis Sokol wrote:
>>> I have a BTI LK-2000 using a 3-1000Z operating on 160. I can get 1250
>>> watts out with 2700 volts and 750 ma key down. The tube seems to be
>>> limited in current draw. I have seen more power out at a different
>>> QTH with higher line voltage.
>>>
>>> I have measured the filament voltage at full load to be 7.08 volts.
>>> This is a bit low from the spec of 7.13 to 7.87 volts. Is the low
>>> filament voltage a possible cause of reduced power out?
>>>
>>> There is a 208 volt tap on the filament xformer but I would have to
>>> put in a dropping resistor in the primary to bring the voltage down
>>> to 7.5 volts. Is it worth the effort? Am I hurting the tube with the
>>> lower filament voltage or am I extending the life?
>>>
>>> Thanks and 73,
>>> Dennis W0JX Milan, OH
>>> _______________________________________________
>>> 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
>>
>>
>
> Richard L. Measures, AG6K, 805.386.3734. www.somis.org
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 0507-2, 02/16/2005
Tested on: 2/20/2005 7:31:06 AM
avast! - copyright (c) 2000-2004 ALWIL Software.
http://www.avast.com
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|