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[NJ3U]

James,

Welcome to the fun filled world of vintage tube equipment !  I also have a earlier model of your amp, mine is a FL-2100.  It is my first tube amp, and I've learned a lot from it by researching, looking, listening and then operating it.

If you haven't found the Foxtrot Tango website yet, check out <<  http://www.foxtango.org/amplifiers/FL%20Amplifier%20Evolution.htm  >> Carol and others have taken the time to capture alot of great information on Yaesu gear, tips and insights galore!  As well there is a Yahoo user community for Foxtrot Tango discussions that cover the FL series.

What has been said here is good advice, I'd add that I have a enclosed "muffin" style fan sitting on my FL-2100 and when I'm operating I flick it on to keep the air moving.  FT amp website URL mentioned earlier has well documented section on vintage fans that are not spinning up anymore due to nicotine and dust bunnies !  Remember, nothing is going to save you from an improperly tuned amp, but the additional moving air sure isn't gonna hurt anything !

Pairs of 572B's can be had for 100$ from RFParts.  I believe that these are the same Chinese tubes sold on Ebay, it's just that RFParts checks them out and they are local US company to deal with. Be careful as there isn't much room inside of the PA compartment to move about and the keying of the tube base is essential !!!

Check out this video tour of tubes being made in China on no doubt original old US machines using processes, materials and practices that our local regs would frown on :-(.  <<  http://www.ks-hifi.com/artical/shuguang/shuguang.htm   >>

73
KC2UML
Rory

[K8AXW]

I've seen only one case of tube envelope "sucking in"..
That was caused by an old man that simply took too long to tune his transmitter that used sweep tubes.

Probably the best advice given here was "Take your time!

[G3RZP]

It's a good idea to get used to tuning a new amplifier by running it into a dummy load via a wattmeter to start with. That way, you can see what you are getting...

[N1UK]

After I have tuned my amp, I record the positions of the Load and Tune controls in a tuning chart by band and frequency.  I have the chart in a Word document at my operating position and I can always set my load and tune controls to almost the exact position for any band/freq before I start tuning.


I have LED peak power/swr meters at the input and output of my amp. It is very useful to see what is going on at all times and the peak reading LED meters allow me to tune by sending a series of cw dits or dahs instead of key down.


73 Mark N1UK

[G3RZP]

I record the positions of the Load and Tune controls in a tuning chart by band and frequency.

Mine is done the old fashioned way on a piece of laminated card, but the principle is the same and it helps rapid band change.