perhaps I am wrong.
I was hoping you could give an alternative explanation for what was reported.
Then we can look over both and possibly come up with other explanations.
Mine was based on what was reported.
I was referring to the picture I posted, being "passive" suckers, so you still need your conventional solder to heat the thing.Not so amusingly the usual cheap solder suckers are not temperature regulated or whatever at all. They cook happily and also need care to use them. Can destroy pads in seconds
Personally I always use desolder braid for anything smaller than, say, TO-247. The cooker takes care of the big ones.
Hannes
BTW, just a nomenclature question, in english language, call you solder both the tool and the consumable?
http://www.howardelectronics.com/amtech/images/63-37-031.jpg
http://www.myopenrouter.com/downloads/newsletter/20100922/solder.jpg
Bear,
I think Andrew was wondering about the relation between the input frequency cut-off and the output DF.
In my experience with single/double layer PCBs, I have found far easier to lift a track on single layer PCB. Somehow, the vias seem to hold both side's tracks attached between them.
On single layer, tracks are hold to the PCB solely by the glue or whatever is it.
Thanks!
I see solder as used in a joint between two or more components.
"to solder" is equivalent to saying : form a joint by soldering.
You can apply solder to a component without joining it to anything. This is normally given the term "tinning".
Similarly you can apply solder to the tool. If the tool is hot enough the solder will melt and flow over the clean metal. The cleaning coming from the action of the flux. Again this is referred to as "tinning".
There is another term given to preparing a soldering tool tip ready for soldering, what is it?
But to plate an item with tin is quite different.
Tin plate can be by electrolysis or by hot dipping, maybe sputtering as well.
Yes, be careful to differentiate between tin and tinning, one is Sn the other is solder and in the old days that meant Pb/Sn.
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afraid not.
Tin is Sn
Old fashioned solder is Pb/Sn in a ratio to do the job required of it.
Electronics normally uses the "eutectic" ratio of 63/37 but there are an infinte number of non eutectic ratios. Plumbers solder is almost the reverse of the eutectic. This gives the solder a wide pasty temperature range and during the pasty stage (as the molten solder cools towards the solid phase) the joint can be wiped or reshaped or moved around. The plumbers "art" is almost lost.
The tool is a soldering iron.
The hot part is the "bit" short for tool bit.
I just do it on one side, which is adequate. You can see the solder on the otherside, it is a hole after all!
Russellc
Language problems: i meant you have to heat one side untill the other side melts too.
Which is more heat than in the single sided case.
You risk also to break the bridge between both sides.
Ihave been doing troubleshooting as a job, bad solder joints is your worst ennemy. Double sided PCB does not help.
Which is more heat than in the single sided case.
You risk also to break the bridge between both sides.
Ihave been doing troubleshooting as a job, bad solder joints is your worst ennemy. Double sided PCB does not help.
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double sided with plated through hole is a bit difficult to clear holes.
Part of the problem is heating the slug of solder in the hole and using that molten slug to transfer heat to the other side, ready for the sook of the removal tool.
Compound that with heavy thickness copper traces that are trying to cool both sides.
Now try using a thicker than usual PCB with thicker than usual traces with PTH and double sided and it is really difficult to clear soldered holes. Virtually impossible to remove multi-legged components without severe overheating.
Don't specify thick PCB and thick traces and double sided.
Part of the problem is heating the slug of solder in the hole and using that molten slug to transfer heat to the other side, ready for the sook of the removal tool.
Compound that with heavy thickness copper traces that are trying to cool both sides.
Now try using a thicker than usual PCB with thicker than usual traces with PTH and double sided and it is really difficult to clear soldered holes. Virtually impossible to remove multi-legged components without severe overheating.
Don't specify thick PCB and thick traces and double sided.
I deal with 4-6-8 layer boards every day, 2oz. outside 1.5 and 1oz inside, power planes everywhere, yea it sucks. But, As Patrick says, try not to make mistakes. I have learned ways around the problem at work and I'm the best at what I do. Trouble is, I'm not supposed to be the rework guy! Easiest best trick, use low temp solder paste instead. 138C liquidous temp. Peice of cake, or, like a fish without a bicycle? Never did figure that phrase out?
Use a small piece of "Music wire" (tungsten I think) rotating against the Iron tip to dig out the hole (requires a microscope for us old farts). Mix the low temp with the wire solder and slosh it around with the iron to alloy it together, it will be easier. Buy tip conditioner for your iron tip. Use it judiciously. nThe tip always needs to be wet, or "tinned". Then go back with the solder wick. I used to use a solder sucker on thru hole, it's easy. Don't cut it on the stuff I do now...
Just my 2 cents
Use a small piece of "Music wire" (tungsten I think) rotating against the Iron tip to dig out the hole (requires a microscope for us old farts). Mix the low temp with the wire solder and slosh it around with the iron to alloy it together, it will be easier. Buy tip conditioner for your iron tip. Use it judiciously. nThe tip always needs to be wet, or "tinned". Then go back with the solder wick. I used to use a solder sucker on thru hole, it's easy. Don't cut it on the stuff I do now...
Just my 2 cents
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M y F5 is now sitting on the workbench warming up with voltage across the source resistors of 0.595V give or take a millivolt but with output offsets of nearlr 140mv and 110mv respectively. I'll let it warm up for an hour and then see if I can tweak P1 & P2 to see if I can get it lower.
Thanks for peoples advise and pointers.
Thanks for peoples advise and pointers.
Nice, you should be very close. At that stage I was showing 500+ mv! A little pot twiddling and you should be done.
Russellc
I don't have exactly the bias identically on both mosfets, I have a bit more in the 9240 than the 240 for get from -1mV to 2mV offset. Usually I have the 9240 at 0,6V and the 240 at 0,58V in one channel and 0,575V in the other.
In ten months of my F5 I don't have any remarkable bias movement (Just I did a readjust at in the first month),usually I do a offset inspection with regularly (every two weeks).
My F5 work 16 hours at day 7 days at week.
Cheers
I've finally got there
After a bit of twiddling of P1 & P 2 I now have about 1mv of offset on both channels with 0.595V across the source resistors. The power supply is running at 23.2V and the heatsinks at 40C; maybe I went over the top with the sinks.Can't wait to have a listen tomorrow.
Thanks for the good comments.
After a bit of twiddling of P1 & P 2 I now have about 1mv of offset on both channels with 0.595V across the source resistors. The power supply is running at 23.2V and the heatsinks at 40C; maybe I went over the top with the sinks.Can't wait to have a listen tomorrow.
Thanks for the good comments.
I've finally got there
After a bit of twiddling of P1 & P 2 I now have about 1mv of offset on both channels with 0.595V across the source resistors. The power supply is running at 23.2V and the heatsinks at 40C; maybe I went over the top with the sinks.Can't wait to have a listen tomorrow.
Thanks for the good comments.
I await your listening comments. You'll love it!
Russellc