'cept by then all broadcast stations will be in orbit...
N7HIY wrote:
> 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
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|