[Amps] Ameritron AL-800

[Steve Thompson]

Unfortunately, plain text doesn't convey the tongue-in-cheek and 
intended humour of my comment (prompted by not long having received the 
info. about the new LDMOS part). Well cared for, tubes will often 
outlive their owners; my 60 yr old 813s probably will.

Nevertheless, a single transistor rated at 3-4kW output is an intriguing 
prospect and would have been the stuff of science fiction when I started 
out in RF design.

Steve G8GSQ

On 09/12/2025 15:34, Steve Bookout, NR4M wrote:
> Have you given any thought to converting to some of the Russian tubes.
> Would justhave to be an easier rebuild than converting to LDMOSFET’s. And, when I last looked those tubes are still less expensive than ‘Merican alternatives.
> 
> Steve NR4M
> 
> Sent from my iPhone
> 
>> On Dec 9, 2025, at 6:03 AM, Douglas L via Amps <amps at contesting.com> wrote:
>>
>> I wouldn’t say that using an LDMOSFET is a retrofit.
>> It would basically mean building an entirely different amplifier with a different power supply, different input and output networks, etc.
>>
>>> On Dec 9, 2025, at 5:32 AM, Steve Thompson via Amps <amps at contesting.com> wrote:
>>>
>>> https://www.ampleon.com/products/extremely-rugged/75-v/ART4K0FX.html
>>>
>>> But not the easiest retrofit 🙂
>>>
>>> Steve G8GSQ
>>>
>>>>> On 09/12/2025 08:37, Douglas L via Amps wrote:
>>>> Has anyone created a work around to replace the 3CX800A7 tubes in the AL-800, the AL800H, Alpha, Ten-Tec and other amps that used this tube?
>>>> Eimac versions are greater than $1500 and the Chinese subs, last I looked, were pushing toward $1000/tube. Machlett, Penta and the like are simply rebranded Chinese tubes.
>>>> Medical pulls have largely dried up with MRI and other machines going solid state.
>>>> Thus the tube pricing has gotten ridiculous.
>>>>   Perhaps the only answer is going to solid state amps?
>>>> 73,
>>>> DougWA1TUT
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