Heck, with the bulbs, it's 600W worth 
The more of them you run, the hotter the heat sink can safely be... Also, the heat sinks I'm planning to use are large, but not very thick, having more resistors will make it easier to spread the heat out on the sinks.
Besides, they're cheap, and non-inductive, so how can you go wrong?
Roscoe
The more of them you run, the hotter the heat sink can safely be... Also, the heat sinks I'm planning to use are large, but not very thick, having more resistors will make it easier to spread the heat out on the sinks.
Besides, they're cheap, and non-inductive, so how can you go wrong?
Roscoe
Option....
Hi Roscoe!
I found Caddock: Power resistor 20 Ω 100 W here at my delivery!
Two of the in paralell gives 10 ohm and then you take 2 pc 2ohm/50 watt to give you 300 watt with 14 ohm.
Or something like this which will keep cost somewhat lower - and the heat acceptable???
Best
Olav
Hi Roscoe!
I found Caddock: Power resistor 20 Ω 100 W here at my delivery!
Two of the in paralell gives 10 ohm and then you take 2 pc 2ohm/50 watt to give you 300 watt with 14 ohm.
Or something like this which will keep cost somewhat lower - and the heat acceptable???
Best
Olav
Hi Roscoe!
I found Caddock: Power resistor 20 Ω 100 W here at my delivery!
Two of the in paralell gives 10 ohm and then you take 2 pc 2ohm/50 watt to give you 300 watt with 14 ohm.
Or something like this which will keep cost somewhat lower - and the heat acceptable???
Best
Olav
not a good idea you will have 35 watt dissipation on a 50 watt resistor , too short , try to find minimum of 100W or use 4 20 ohm , remember i use 1 800W 10 ohm resistor and my heatsink is still very hot with 75W off dissipation on it
not a good idea you will have 35 watt dissipation on a 50 watt resistor , too short , try to find minimum of 100W or use 4 20 ohm , remember i use 1 800W 10 ohm resistor and my heatsink is still very hot with 75W off dissipation on it
Hi Juanitox!
Yea - I know very well - but with 2 in parallell = 2x 100= 200 watt plus 2 50 watt (or make it 100 watt) = 200 + 100(or 200)= 300watt (or400watt).
So you get really close with this - I believe.
Have to run - my helicopters to shore will leave soon
Olav
I have a case for the F5 or F4 with adequate heatsinks and these are sufficient for the SK and the resistors.
Olaf I think your values are o.k. regarding the heat, I have the same wattage combined, only difference, I used four 10 Ohm/50W to make the ten Ohm as a starting point for the resistor chain.... so the heat is still a bit more diversified...
but I do not think this is necessary....
Juanitox is your machine ready and sounds.....?
i 'm finishing mounting the Rifa and power choke , and R-core transfo in my little chassis ... it will sounds or not this weekend 
sure you re right but bulbs are not a good idea with a daughter playing football in the living room
Certainly a consideration.
I am just going to receive 4 pieces of 500w incandescent bulbs from italy . 220 volt . Just for the taste of trying them since I am always using halogen type .
not a good idea you will have 35 watt dissipation on a 50 watt resistor , too short , try to find minimum of 100W or use 4 20 ohm , remember i use 1 800W 10 ohm resistor and my heatsink is still very hot with 75W off dissipation on it
How hot your heat sink gets is a function of the amount of power it's dissipating, not the power rating of the resistor..
Roscoe
SIT amp V.3 ready to tun it on .... ZAbooooom 
i explode my amp again , a little smoke go out , i stop and mesure the B+ i have 50 V , look at my bias module 25V after the diodes ..and nothing on both lm337 ..they fried , i think i must lowered the 20V AC with a res to use them . any idea
on the current of the bias ?
so i rewire my sit with the gate on earth and 1ohm resistor on the source . turn on ...
sounds here again and what a sound!! no more hum or buzz with the R-CORE transfo and CLC filtering . i'v got 16V and 2.3 amp not so bad . pure pleasure . i will listen like this this week end before returning to negative bias french sit V.3
An externally hosted image should be here but it was not working when we last tested it.
Merveilleux Monsieur!
Congratulations to version 3! and welcome in the club to make faults from time to time...
With negative bias you can try a 9V block and let him connected........so you cannot forget to connect him.
He will live with the correct voltage at least 5-7 days. Mine went in this time from 9.6 to 8.6V......
what kind of speakers are you driving?
Congratulations to version 3! and welcome in the club to make faults from time to time...
With negative bias you can try a 9V block and let him connected........so you cannot forget to connect him.
He will live with the correct voltage at least 5-7 days. Mine went in this time from 9.6 to 8.6V......
what kind of speakers are you driving?
a german speaker nobody is perfect ...
An externally hosted image should be here but it was not working when we last tested it.
