Sorry to ask such an elementary question.
What is the Plate load for a single 7236 in Push Pull?
And along the same lines, what's the Plate load for a Pair of 7236's in PP?
Each tube with its triodes paralleled of course.
Also expected watts out?
What is the Plate load for a single 7236 in Push Pull?
And along the same lines, what's the Plate load for a Pair of 7236's in PP?
Each tube with its triodes paralleled of course.
Also expected watts out?
Draw a load line, and do the calculations. With respect you'll learn more by finding out for yourself rather than using someone else's brain.
Andy.
Andy.
Well maybe I'm having trouble with that. Which is why I asked for help.
But thanks for your reply.
Not helpful though it was.
There are many plate loads that would work. Rp is roughly 400 ohms, so a 4-5K p-p transformer is where I would start in terms of drawing load lines. I would run the tube at 250V and 60mA per triode.
Hmmmm ... 250V at 60mA is 15W plate dissipation, right on the maximum rating for the 7236. They are not a very common valve and replacements can be hard to find, so it might pay to run them a little less hard.
Here's a link with a worked example of a push-pull triode loadline calculation (it's for triode-connected 6550s - the method is generally applicable: loadmatch-3-PP-triodes).
You could try 250V and 50mA as a quiescent operating point for 12.5 Watts dissipation rather than 15 Watts. That's about -50V grid bias.
Have a go at calculations for a push-pull output transformer with an 8kOhm primary impedance, see how many Watts output power you estimate. Then repeat for 5kOhm. Both results should be respectable.
Here's a link with a worked example of a push-pull triode loadline calculation (it's for triode-connected 6550s - the method is generally applicable: loadmatch-3-PP-triodes).
You could try 250V and 50mA as a quiescent operating point for 12.5 Watts dissipation rather than 15 Watts. That's about -50V grid bias.
Have a go at calculations for a push-pull output transformer with an 8kOhm primary impedance, see how many Watts output power you estimate. Then repeat for 5kOhm. Both results should be respectable.
Sorry, sometimes we need a friendly kick up the arsenvenga, else we'd all still be running around chasing woolly mammoth's with pointy sticks: have a look here - How to design valve guitar amplifiers all, well a lot, of the info one needs to build an amp. Drawing a load line isn't hard, like anything it takes practice, but if your building and designing an amp your going to have to get your thinking cap on and do at least a few calculations.
Andy.
Andy.
It can't be much different from 2A3 or 6080. The higher Mu affects bias and drive but not so much power relations.
If you stay Class A, the single side load is a-a/2. The easiest way to see if you're going to go AB is graphically. Dot the idle point, and draw a line at slope of a-a/2. If the bit to the right hits the zero current spot before the bit on the left hits g1=0V then change the slope to a-a/4.
cheers,
Douglas
cheers,
Douglas