Hi in these pre-christmas time!
Hi all!
Just to have a note before the holiday: my old schoolteaching tells me - if you have a halogen bulb with 24 volt and 100 watt = 24x24=576 divided on 100 = 5,76 ohm!! Then you have 3 in seriell= 17,28 with 300 watt. If you then keep 3 more in paralell to those first 3 you end up with 600 watt AND 8,64 ohm. That is pretty close - and if you give 1 resistor in seriell with those bulbs - you get even closer. I have found som small bulbs(halogen 100 watt, 24 volt) here in Norway.
My SK82(KD33) was ordered 1 week ago. so the build will start in feb/mars!
Happy New Year
Greetings to all
Olav
Hi all!
Just to have a note before the holiday: my old schoolteaching tells me - if you have a halogen bulb with 24 volt and 100 watt = 24x24=576 divided on 100 = 5,76 ohm!! Then you have 3 in seriell= 17,28 with 300 watt. If you then keep 3 more in paralell to those first 3 you end up with 600 watt AND 8,64 ohm. That is pretty close - and if you give 1 resistor in seriell with those bulbs - you get even closer. I have found som small bulbs(halogen 100 watt, 24 volt) here in Norway.
My SK82(KD33) was ordered 1 week ago. so the build will start in feb/mars!
Happy New Year
Greetings to all
Olav
Olav
I was talking about 300W/120V bulbs, not 24V.
O.K. maybe a way to go.
Thanks for all answers up to now.
Franz
I was talking about 300W/120V bulbs, not 24V.
O.K. maybe a way to go.
Thanks for all answers up to now.
Franz
Hi Franz
Yeah - I know that it would be a closer fit with 300watt and 120 volt, but it is somewhat difficult to get hold on 120 volts bulbs here in Norway - and with 230 volt and low wattage bulbs it is even vorse(like 230 watt and 20 or 10 watt)!
That is why I am thinking to try my amp with those 24/100 watt bulbs? Maybe?
Best to all.
Olav😕
Yeah - I know that it would be a closer fit with 300watt and 120 volt, but it is somewhat difficult to get hold on 120 volts bulbs here in Norway - and with 230 volt and low wattage bulbs it is even vorse(like 230 watt and 20 or 10 watt)!
That is why I am thinking to try my amp with those 24/100 watt bulbs? Maybe?
Best to all.
Olav😕
don't you think this kind of filament could be inductive?!
An externally hosted image should be here but it was not working when we last tested it.
so litlle ....
Hi again!
Here is my finding: From the ELFA catalog: 4000 HOURS!!!
: https://www.elfaelektronikk.no/elfa3~no_no/elfa/init.do?item=33-534-48&toc=19002
A search gave me this result - maybe it can be that i nyour country too??
Good luck - and the best to you.
Olav🙂
Hi again!
Here is my finding: From the ELFA catalog: 4000 HOURS!!!
: https://www.elfaelektronikk.no/elfa3~no_no/elfa/init.do?item=33-534-48&toc=19002
A search gave me this result - maybe it can be that i nyour country too??
Good luck - and the best to you.
Olav🙂
Out of sheer morbid curiosity, I tested a large source resistor bypass cap (47,000 uF) and the results were not especially good. 1W THD climbs from .07% to around .5%.
I didn't listen to the amp with the bypass capacitor. In my case, the added distortion wasn't worth 3-4 dB of gain, so I didn't pursue it further.
You leave me a little perplexed. The source bypass cap does not make direct coupling the input any more or less possible. The input cap is there in Figure 11 in case your SIT has enough gate leakage current to drop some voltage across the input. If you measure the input, and it is at 0V, then perhaps you can go without.
May I suggest building the circuit as intended, getting it working, and then you can experiment and make sparks as much as you wish.
If you really want more gain and no degeneration, the circuit with the negative bias supply is the way to go.
You leave me a little perplexed. The source bypass cap does not make direct coupling the input any more or less possible. The input cap is there in Figure 11 in case your SIT has enough gate leakage current to drop some voltage across the input. If you measure the input, and it is at 0V, then perhaps you can go without.
May I suggest building the circuit as intended, getting it working, and then you can experiment and make sparks as much as you wish.
If you really want more gain and no degeneration, the circuit with the negative bias supply is the way to go.
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i mean i choose fig 11 instead of fig 10 because i can swap the input Cap and the negative bias circuit.. but if it must sound bad as it , i will change to fig10
with this
is there a problem just to have 10ohm resistor for the drain ? or is it must be 11/12ohm 🙂
with this
An externally hosted image should be here but it was not working when we last tested it.
is there a problem just to have 10ohm resistor for the drain ? or is it must be 11/12ohm 🙂
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10 Ohms will change the operating point, you can certainly try it though.
Are your speakers 8 Ohms?
Are your speakers 8 Ohms?
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Wow, those should sound terrific. Try the 10 Ohm. It's easy enough to add some resistance if needed.
thanks michael , sorry to be the dumb and dumber of your post😀
do you think i still can use the 25k gate leak that i have already sold and mount on the 2SK82 with the LM337 schematic?😕
do you think i still can use the 25k gate leak that i have already sold and mount on the 2SK82 with the LM337 schematic?😕
No worries. We're all here to learn and have a little fun hopefully.
I'm sorry I don't understand your question.
I'm sorry I don't understand your question.
