Doubling the voltage. The 76 voltage is too low for the 8877.
73
Bill K5FUV
Sent from Yahoo Mail for iPad
On Wednesday, November 6, 2019, 3:48 PM, Steve London <n2icarrl@gmail.com>
wrote:
Okay....I'll be stupid....
Besides the filament voltage and socket, what else would it take to convert
something like a 3 tube Alpha 76 to a single 8877 ? Seems like the output Z is
in the right ballpark.
73,
Steve, N2IC
On 11/06/2019 02:26 PM, Jim wrote:
> Agreed! 8877 is one the the BEST tubes for ham radio.
>
> LOTS of them out there and available. Hams bought many of them for spares
> that
> never got used; Because the 8877 was such a robust tube. Most 8877 tubes got
> babied... Except for contesting... But there is testimonial from K3LR's large
> and busy contest station below. So even in a contesting environment, the 8877
> goes STRONG!
>
> 8877/3CX1500A7 hard to beat!
>
> Thanks
> 73
> Jim W7RY
>
> On 11/5/2019 8:34 PM, Tim Duffy wrote:
>> Hello Jim,
>>
>> I agree - the 8877 - 3CX1500 is a VERY good Ham Radio tube. I have several
>> in
>> service here at K3LR that are 30 years plus years old.
>> 18 amplifiers here using 8877s that make 1500 watts output RTTY with high TX
>> duty cycle - no problem - all the way to 220 MHz!
>>
>> The 8877 is an excellent engineered tube for amateur radio - easy to build
>> amplifiers with the 3CX1500A7.
>>
>> 73
>> Tim K3LR
>>
>> -----Original Message-----
>> From: Amps [mailto:amps-bounces@contesting.com] On Behalf Of MU 4CX250B
>> Sent: Tuesday, November 5, 2019 9:12 PM
>> To: Carl
>> Cc: amps@contesting.com
>> Subject: Re: [Amps] GS35B Amps Common Problem / few more comments
>>
>> You may be a bit harsh, Carl! I’ve lost two 8877s in the past half
>> century or so, and it was my fault both times. The first was when I
>> stupidly let the filament voltage drop way below specs, and the second
>> was when the blower on my Alpha 9500 failed and I didn’t notice for
>> two weeks. My workhorse homebrew amp, built in the 1970s, has an Eimac
>> 8877 with a 1978 date code. Still full output, 4300V on the anode.
>> 73,
>> Jim w8zr
>>
>> Sent from my iPhone
>>
>>> The 8877 is a fragile short life wannabee befitting an oxide cathode tube
>>>
>>>
>>> Carl
>>>
>>>
>> _______________________________________________
>> 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
>
> _______________________________________________
> 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
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|