[Amps] Building an amp suggestions

[Bill Turner]

ORIGINAL MESSAGE:          (may be snipped)

On 5/3/2014 3:16 PM, glenn riccio wrote:
> Hi every one , I am contemplating building another QRO amp. Several years
> ago , I built a GG amp using a pair of 3-500z"s. Very conventional but it
> works very well. I now have the urge to build another amp. I am considering
> using a 4-1000 but I have read that it probably isn't the best choice for GG
> service. Then I thought about  class AB1. That also has its drawbacks as I
> understand neutralization can be tough to get right. Since 99% of my
> operating is CW, maybe a class C is the way to go.
>
>    Does any one have any suggestions as to the best tube to use other than
> 4-1000 ?  Any ideas would be helpful. Thanks es 73 de K7GFR  Glenn
>
> _______________________________________________

REPLY:

You're sure to get a lot of feedback on this.

Having built five 1500 watt amps from scratch with varying degrees of 
success, here are my suggestions:

1/ Use class AB1. Properly designed with short connections as much as 
possible, GG amps don't need neutralization when using  triodes.

2. Best tube, IMO, for legal limit is the 8877. More expensive than some 
tubes, but the Chinese ones on eBay do fine for about $500. Mine has 
been in my amp for going on five years with no trouble, still full output.

3. Don't skim on the bandswitch or the tune and load capacitors. A good 
bandswitch costs between $300 and $400 if bought brand new, and the best 
caps are vacuum variables, which I buy used from Max Gain Systems. Turns 
counters from Palstar.

If there are any other questions, feel free to ask.

73, Bill W6WRT