Search found 5599 matches

by simon
Sun Mar 28, 2010 7:36 pm
Forum: Beginners
Topic: Loadlines - voltage swings and driving valves (6EM7 again)
Replies: 22
Views: 7300

...so the net effect on the load line is the actual grid voltage in is less that it seems, so a loss in gain, and given that ra, µ, and gm are linked, reducing gain while leaving gm the same will mean ra has to increase Okay, think I get it. Basically, an unbypassed cathode resistor has the effect ...
by simon
Sun Mar 28, 2010 1:11 pm
Forum: Beginners
Topic: Loadlines - voltage swings and driving valves (6EM7 again)
Replies: 22
Views: 7300

I had a read of MJ last night and he says that not bypassing the cathode resistor increases the valve's anode resistance. Presumably this flattens the plate curves (V against I) but how would I plot loadlines etc. and work out swing if the curves aren't the same? Or is there a trick somewhere? Sorry...
by simon
Sat Mar 27, 2010 9:51 pm
Forum: Beginners
Topic: Loadlines - voltage swings and driving valves (6EM7 again)
Replies: 22
Views: 7300

Not sure I've understood this - does this mean that only a small turn on the volume pot might drive the amp to full output though? Presumably 2VRMS on the input will overdrive the output valve? Yes, it does mean this, but if 0.5v RMS is all it needs to overdrive the output stage, the input will nev...
by simon
Fri Mar 26, 2010 9:05 pm
Forum: Beginners
Topic: Loadlines - voltage swings and driving valves (6EM7 again)
Replies: 22
Views: 7300

Not sure I've understood this - does this mean that only a small turn on the volume pot might drive the amp to full output though? Presumably 2VRMS on the input will overdrive the output valve?
by simon
Fri Mar 26, 2010 6:40 pm
Forum: Everyones Projects
Topic: Beercan amp
Replies: 4
Views: 3206

This reminds me of an Ivimey special using a redundant tin of Quality Street knocked up for a do some years ago. A keg of beer is somehow much more rock and roll though.
by simon
Thu Mar 25, 2010 1:14 pm
Forum: Buying and Selling
Topic: Wanted - Mains TX for 6EM7 amp !
Replies: 23
Views: 6988

Manvile You've definitely been in there then! I had 10 pints in there after the first exam of my finals - it was Structures and a nightmare. It was a Friday so I had the weekend before the next one. I'd forgotten about that, but somehow look back fondly now with a smile on my face :). That sounds l...
by simon
Thu Mar 25, 2010 12:19 pm
Forum: Buying and Selling
Topic: Wanted - Mains TX for 6EM7 amp !
Replies: 23
Views: 6988

Thats the Rawal, still a great place to eat. I don't remember it being called that, but memory's a funny thing. Good to know it's still a good curry though. On the mild side if I remember correctly but the onion bhajis were particularly good? I drove through that part of Bradford a couple of years ...
by simon
Thu Mar 25, 2010 12:13 pm
Forum: Buying and Selling
Topic: Wanted - Mains TX for 6EM7 amp !
Replies: 23
Views: 6988

Don't remember the Shimla - were was it? Directly opposite where the Shearbridge halls used to be, opposite the junction of Shearbridge road and Gt Horton road. http://www.google.co.uk/maps?f=q&source=s_q&hl=en&geocode=&q=shearbridge+road&sll=53.800651,-4.064941&sspn=15.3204...
by simon
Wed Mar 24, 2010 9:44 pm
Forum: Buying and Selling
Topic: Wanted - Mains TX for 6EM7 amp !
Replies: 23
Views: 6988

Don't remember the Shimla - were was it?
by simon
Wed Mar 24, 2010 9:43 pm
Forum: Buying and Selling
Topic: Wanted - Mains TX for 6EM7 amp !
Replies: 23
Views: 6988

I remember when the International opened 20-odd years ago - went in a lot. Used to do a great chicken and mushroom curry back when I used to eat meat. Last time I went was maybe a year ago and was a bit disappointed. What's the one round the corner from the Kashmir called? Opposite the City mortuary...
by simon
Wed Mar 24, 2010 9:04 pm
Forum: Buying and Selling
Topic: Wanted - Mains TX for 6EM7 amp !
Replies: 23
Views: 6988

PeteC wrote:P'raps a few of us can combine a listening session with a curry down Horton Road afterwards sometime ?
Ahhh, my old stamping ground :). It's a bit different down there these days though I think. Proper tables and wallpaper and stuff.
by simon
Wed Mar 17, 2010 8:04 pm
Forum: Assorted Stuff
Topic: SimonFest
Replies: 80
Views: 22896

when are you going to start a photography masterclass? You're too kind Ed :). Good photography requires good technical skills and good compositional skills. I have a sound understanding of exposure basics and use a camera with more computing power than an old space mission to do the hard work for m...
by simon
Tue Mar 16, 2010 10:48 pm
Forum: Assorted Stuff
Topic: SimonFest
Replies: 80
Views: 22896

Back to the front room an Steve's 801A amp and baffles http://i57.photobucket.com/albums/g201/simon2a3/Simon%20C%2010-03-14/13.jpg http://i57.photobucket.com/albums/g201/simon2a3/Simon%20C%2010-03-14/14.jpg Back to the back room and Nick's 211 amp with Colin's Chilinghams http://i57.photobucket.com/...
by simon
Tue Mar 16, 2010 10:40 pm
Forum: Assorted Stuff
Topic: SimonFest
Replies: 80
Views: 22896

A couple more http://i57.photobucket.com/albums/g201/simon2a3/Simon%20C%2010-03-14/09.jpg http://i57.photobucket.com/albums/g201/simon2a3/Simon%20C%2010-03-14/10.jpg And two more, now with Colin's TJ 300Bs http://i57.photobucket.com/albums/g201/simon2a3/Simon%20C%2010-03-14/11.jpg http://i57.photobu...
by simon
Tue Mar 16, 2010 10:36 pm
Forum: Assorted Stuff
Topic: SimonFest
Replies: 80
Views: 22896

Next was Andrew I's OTL (got some decent photos for you this time Andrew) http://i57.photobucket.com/albums/g201/simon2a3/Simon%20C%2010-03-14/06.jpg http://i57.photobucket.com/albums/g201/simon2a3/Simon%20C%2010-03-14/07.jpg And then it was on to Mike's 801A amp http://i57.photobucket.com/albums/g2...