-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
Ebay AL-811H, What Have I done?
- Thread starter 338_MtRushmore
- Start date
RF Parts has a matched quad of Taylor 572B's for #319.80 or the cheaper PRC tubes at $44.95 each if you are not worried about a matched set. Single Taylors are $79.85 or you could go with their limited NOS Cetrons at $199.95 EACH. LOL The matched Taylors are a bit more than twice the price of the 811A's but then again they have two and a half times the plate dissipation rating too.
The Taylor 572b is $80 and the 811a prc is $55. What is the advantage of the 572b over the prc? Plate dissipation on both are 160 watts.
I keep seeing to keep the key time under 5 seconds with a 15 second cool down when tuning. Would the 572b or PRC allow me 10 or 15 seconds of key? That could make sense to spend the extra money to tune much faster.
I keep seeing to keep the key time under 5 seconds with a 15 second cool down when tuning. Would the 572b or PRC allow me 10 or 15 seconds of key? That could make sense to spend the extra money to tune much faster.
I ran mine at 240 as I do my ICOM PW-1.Never any issues.Also I purchased the 811A tubes from Ameritron & they never had an issue.
SIX-SHOOTER
The 572B has a 160 watt plate dissipation rating whereas the 811A has a plate dissipation of only 65 watts. The numbers I stated above ARE correct. Either you misread the ratings on the RF Parts site or they screwed up. Wait.............I just checked RF Parts. That PRC 811A for $55 is rated at 160 watts. They claim it has a "graphic" plate which I take to mean graphite plate. Note they are available only in limited quantities. IIRC there were some 572Bs that were made that would NOT handle full plate voltage that the 572B should due to closer element spacing. I believe they were relabeled as heavy duty 811As and are to only be used as a replacement for 811As due to the lower voltage ratings.
Welcome to "How to blow your ham Radio Budget" 101.
Nomad and Captain Kilowatt are the two best tube aficionados I know of,
Well I'll put it this way, not many that I would take amps to beside myself.You must not know many people do you.
I had an AL-811 for several years. With reasonable care in tuning it up you shouldn't have any problems. You can almost buy 2 sets of 811A tubes for the cost of the 572B tubes.
Only problem I had with the amp was it needed more padding capacitance on 80 meters. Easy fix.
I have an AL-80B now. Much nicer amp and much quieter too.
Only problem I had with the amp was it needed more padding capacitance on 80 meters. Easy fix.
I have an AL-80B now. Much nicer amp and much quieter too.
811A's are fine for sensible SSB use but for balls to the wall 11m use or on AM they are a poor choice.Even W8JI the designer of most of the Ameritron amps admits the 811A's are being used beyond their design limits but for SSB voice service it is not a big issue. Take too long tuning up or running AM however is another issue.
I just saw it didn't come with any tubes.
I wouldn't have paid that much for it but that is water under the bridge.
I wouldn't have paid that much for it but that is water under the bridge.