Home |
Search |
Today's Posts |
|
#1
![]() |
|||
|
|||
![]()
In article , "Ian White, G3SEK"
writes: Michael Black wrote: Perfboard was around long before most hobbyists had heard of wire wrap. Once transistors came along, perfboard tended to be the method of construction, unless you were planning to do it point to point on a chassis like you would with tubes. "Messy" has no relevance since the wiring was under the board. You'd use component leads to connect the parts, and if they weren't long enough, bits of wire. That's right... Maybe it would help to give an example where plain perfboard was the best construction method. I recently built a small power distribution board which involved four 0.1in-pitch connector headers, a voltage regulator IC and a few passive components. Why choose plain perfboard for this project? Mostly because the wiring underneath was going to be fairly complex, so hand-wiring was going to be the easiest way to make the board reasonably small. The advantage of hand-wiring is that you can have as many crossovers as you like, using insulated wire. What other techniques didn't I choose? Even a double-sided PC board would have needed some jumpers, and wouldn't have been worth the effort for a one-off project. A single-sided PC board would have required lots of jumpers, and copper-strip perfboard (Veroboard/Vectorboard) would have been even worse. So bare perfboard it was. The four headers were temporarily superglued onto the board, so they wouldn't fall out when the board was turned over to do the wiring. Under the board, I ran a common ground bus of 18SWG/16AWG tinned copper wire around all the headers. The other small components were pushed through the holes, and anchored by their leads as the various connections were made. Most of the wiring was done point-to-point using the bare component leads. Crossovers were handled using kynar insulated wire - sold for wire-wrapping, but excellent for point-to-point soldered wiring too. By the time all the header pins had been soldered to, the headers were well anchored through the board and are very secure. The whole thing looks quite tidy from the top. If neatness is important (and indeed, why not make a good job of it?) the main consideration is to cut the board cleanly and file off the ragged edges. Ian, I'm in perfect agreement with what you and Michael Black wrote. I base that on working prototypes made for over three decades. It seems as though perfboard has been around longer...:-) One thing that all should remember: Electrons don't care about "neat" construction. "Neat" gets something past inspectors, appeals to customers, looks mighty fine and "professional" in photographs. Electrons don't care for any of that. Fields and waves only care about placement of conductors and nearby dielectric material. And the ones with bits of copper at each hole had the advantage, as someone pointed out, that you could solder the components to the board before adding the wires. People were hesitant to make their own etched circuit boards, and even after they became fairly common in hobby circles, many would say "I don't want to bother" and they'd stick with perfboard. Perf and hand wiring SAVES TIME. Homebrewing is about making electronic things at home. Few of us have TIME at our disposal. For relatively simple circuit arrangements, it would take me (somewhat experienced) more time to sketch out a PCB foil pattern and check it against a schematic than direct-wiring a perf-board circuit. A PCB still has to be masked and etched and cleaned. Printed circuit boards originally were a tremendous advantage in mass production of electronics. It could physically hold components as well as perfectly reproduce wiring paths...compared to the longer time needed to mount (vacuum tube style) components and then hand-wire all the connections, usually in several stages of wiring by different assemblers. Production costs dropped considerably once all got through the capital equipment expenditure for PCB machinery. SMT got a big following because it was small...but also because it cut down on production even more. Fewer holes to drill (sometimes none) and the "baking" ovens didn't need as much maintenance as the flow soldering machines did with peanut oil, cleaner and degreaser, solder solutions. SMT took the basic PCB construction technique. Certainly... and as I just said, it's one of the preferred techniques for one-off construction. If perfboard faded from view in recent years, it's likely because etched circuit boards have tended to take over, if not made by the hands of the hobbyist then because people were buying premade circuit boards. Maybe plain perfboard just hasn't had much publicity. As an author, I can see why: if it's a fairly basic 'follow these instructions' project, then at the very least you're expected to design a PC board; but if it's a project for experienced constructors, you don't need to tell them how to build it. In either kind of article, plain perfboard probably doesn't get a mention... but it's still there. Perf with hand-wired "solder side" connections doesn't photograph well. Image is important in magazine layout. :-) As someone pointed out, perfboard is not so great for RF. Better to use a blank piece of copper circuit board, and build on top of that, so you have the copper as a good ground point. Yep. The strengths of plain perfboard are for DC, audio and slow logic circuits, and in the sheer versatility of hand-wiring underneath the board. Right on! But...if one is familiar with RF layout through experience and a "feel" for lead placement and lengths, perf can be used on up to 70 MHz. That is NOT recommended for beginners who have just memorized Ohm's Law. At RCA EASD in the 1970s we regularly used Douglas Electronics 11-DE-1 boards for prototyping digital logic at equivalent clock rates up to 10 MHz. Those held 12 DIPs had three-hole pads and #24 or #26 insulated wire did the interconnects on the component side. A 44-pin edge contact allowed plug-in assembly and extenders. That was most excellent for churning out 1- to 3-of-a-kind prototypes at up to 150 cards per system. Techs could just follow a schematic and hand-wire the cards...sort of "connect the dots" kind of operation. Was very good with few errors done by anyone. Douglas is still in business and the 11-DE-1 prototype board is still available in the USA at about $12 each. A comparable Vector Electronics prototype board is about the same price. I prefer the Douglas since it is gold-flashed and a variant is available with a ground plane on the component side. But that's likely "messier" than using perfboard with the wiring on the bottom. Of course, from time to time I've used copper circuit board as "perfboard", drilling holes where needed and reaming out the copper from around the holes so the components go in without shorting. Wire up on the non-copper side of the board, like perfboard, but all ground connections go to the copper on the top side. If all the grounds are to the common top-side groundplane, it doesn't look messy at all. The top-side looks very neat and the wiring underneath is simplified by the absence of ground wires. Above all, the RF performance will probably be very good. For this kind of project, I very often use PCB design software to work up the layout, but don't always etch a board. Just as often, I cut a piece of single-sided board, tape a 1:1 printout of the PCB design onto the board and use it as a drilling template. Then I hand-wire the underside using the layout as a guide. I cheat a bit. Originally an illustrator, I sketch out the foil paths on vellum 1:1, mark the drill holes and use the vellum as a small center-punch guide. The paths are then painted in with lacquer, free-hand, using the vellum as a guide. Lacquer can be peeled off after etching with a sharp graphics knife (an X-Acto modeller's knife to olde-tymers) and dissolved in acetone to be reused later. Lacquer works fine with ferric chloride etchant. Enamel does NOT. Enamels, now common in aircraft model shops can be undercut in the etching. One has to really hunt for low-enough-price lacquer now but it once was standard "dope" for modelers. I'm still using a half-pint bottle of Testor's model airplane Dope obtained in 1947 (Testor's wisely changed the name slightly after that). Acetone in pint can sizes is available in U.S. do-it-yourself stores. :-) Len Anderson retired (from regular hours) electronic engineer person |
#2
![]() |
|||
|
|||
![]()
Avery Fineman wrote:
One thing that all should remember: Electrons don't care about "neat" construction. "Neat" gets something past inspectors, appeals to customers, looks mighty fine and "professional" in photographs. Electrons don't care for any of that. Fields and waves only care about placement of conductors and nearby dielectric material. [...] Right on! But...if one is familiar with RF layout through experience and a "feel" for lead placement and lengths, perf can be used on up to 70 MHz. That is NOT recommended for beginners who have just memorized Ohm's Law. Wish I knew how to pass on that "feel" for RF layout to other people. It's easy to explain to someone why their existing layout doesn't work, but more difficult to make positive recommendations so their next attempt *will* work. I once wrote an article about that for RadCom, which was lifted by the ARRL Handbook and survived for some years as part of the Construction chapter as 'From Schematic to Working Circuit'. That chapter, taken as a whole, is a pretty good basic reference. But in the end, there's no substitute for your own experience. Just build and build and build. Notice what works, and what doesn't... and then the trick is to understand why. For this kind of project, I very often use PCB design software to work up the layout, but don't always etch a board. Just as often, I cut a piece of single-sided board, tape a 1:1 printout of the PCB design onto the board and use it as a drilling template. Then I hand-wire the underside using the layout as a guide. I cheat a bit. Originally an illustrator, I sketch out the foil paths on vellum 1:1, mark the drill holes and use the vellum as a small center-punch guide. The paths are then painted in with lacquer, free-hand, using the vellum as a guide. The lack of those paper-graphics skills is why I use the PCB software. Heck, I even use it for roughing-out stripboard layouts, to try to maximize the use of the strips. In Europe there's a gadget called a Dalo resist pen which is made specifically for hand-drawing on PCBs. It has a fine fibre tip and very thick, quick-drying ink. It's very expensive for what it is (namely a not very good fibre-tip pen) but with care it can be quite effective. As many people already know, the Staedtler marker pens (waterproof/ wasserfest grade) are excellent for touching-up photo and iron-on resist patterns, but they're not as good as the Dalo for filling large areas. -- 73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB) Editor, 'The VHF/UHF DX Book' http://www.ifwtech.co.uk/g3sek |
#3
![]() |
|||
|
|||
![]()
In article , "Ian White, G3SEK"
writes: In Europe there's a gadget called a Dalo resist pen which is made specifically for hand-drawing on PCBs. It has a fine fibre tip and very thick, quick-drying ink. It's very expensive for what it is (namely a not very good fibre-tip pen) but with care it can be quite effective. As many people already know, the Staedtler marker pens (waterproof/ wasserfest grade) are excellent for touching-up photo and iron-on resist patterns, but they're not as good as the Dalo for filling large areas. I'll add something from the machine shop that is probably in the UK as well: Marker lacquer used to make marks on metal about to be machined. Over here it is usually a deep blue and is very dilute lacquer, obvious from the acetone odor. Various brands, some are available in red or green (not good colors). Scribes nicely. Brushes well with small brushes available from craft stores. From the drafting department of old: K&E ink pens, the two-part cylindrical, concentric ones. Those will hold dilute lacquers and there is a pen holder that takes the nibs. Must soak them in acetone after using since the capilliary clearance is tiny. With practice those pens can draw straight lines but any dilute lacquer likes to migrate to the straightedge...:-) Office Depot and Office Max chains over here carry the Sanford "Sharpie" pens (permanent marker type) whose ink is ferric chloride resistant. I find it difficult to maintain a fine nib on those for small foil lines and prefer a small brush. Mileage varies. I once tried acetone-diluted liquid rosin as a resist, had mixed results. Nice odor combination while doing it. :-) As always, with any kind of resist, the unetched copper surface must be clean and oxide free, smooth in order to take the resist evenly. Len Anderson retired (from regular hours) electronic engineer person |
#4
![]() |
|||
|
|||
![]()
Have had reasonable success using the "Sharpies." What kicks me is way back
when, when I bought a PCB kit from the Shack, I tried to make one and the ink came right off. I gave up - I was still young and stupid, but it was the ink that failed. A few years later, I decided to give it another go, using sharpies after reading some others having used them. I did nothing else different. The success was in the pen. Had I tried a different pen way back when, instead of giving up, I could have been very good at it by now, rather than OK. I have made a few PC boards and though "my" artistic talent isn't that great, the boards came out ok and work as intended. When I do decide to make a project, I actually enjoy going through the whole process including making the board. It is fun to go from nothing to a working item. I've made some test equipment for my shop that has saved me a few hours time already and paid for themselves in parts, time and effort. Just out of curiosity, anyone else buy the Shacks PCB kits and have any problems with the pens? OR solution? For me, the solution has been ok. MNS "Avery Fineman" wrote in message ... In article , "Ian White, G3SEK" writes: In Europe there's a gadget called a Dalo resist pen which is made specifically for hand-drawing on PCBs. It has a fine fibre tip and very thick, quick-drying ink. It's very expensive for what it is (namely a not very good fibre-tip pen) but with care it can be quite effective. As many people already know, the Staedtler marker pens (waterproof/ wasserfest grade) are excellent for touching-up photo and iron-on resist patterns, but they're not as good as the Dalo for filling large areas. I'll add something from the machine shop that is probably in the UK as well: Marker lacquer used to make marks on metal about to be machined. Over here it is usually a deep blue and is very dilute lacquer, obvious from the acetone odor. Various brands, some are available in red or green (not good colors). Scribes nicely. Brushes well with small brushes available from craft stores. From the drafting department of old: K&E ink pens, the two-part cylindrical, concentric ones. Those will hold dilute lacquers and there is a pen holder that takes the nibs. Must soak them in acetone after using since the capilliary clearance is tiny. With practice those pens can draw straight lines but any dilute lacquer likes to migrate to the straightedge...:-) Office Depot and Office Max chains over here carry the Sanford "Sharpie" pens (permanent marker type) whose ink is ferric chloride resistant. I find it difficult to maintain a fine nib on those for small foil lines and prefer a small brush. Mileage varies. I once tried acetone-diluted liquid rosin as a resist, had mixed results. Nice odor combination while doing it. :-) As always, with any kind of resist, the unetched copper surface must be clean and oxide free, smooth in order to take the resist evenly. Len Anderson retired (from regular hours) electronic engineer person |
#5
![]() |
|||
|
|||
![]()
Have had reasonable success using the "Sharpies." What kicks me is way back
when, when I bought a PCB kit from the Shack, I tried to make one and the ink came right off. I gave up - I was still young and stupid, but it was the ink that failed. A few years later, I decided to give it another go, using sharpies after reading some others having used them. I did nothing else different. The success was in the pen. Had I tried a different pen way back when, instead of giving up, I could have been very good at it by now, rather than OK. I have made a few PC boards and though "my" artistic talent isn't that great, the boards came out ok and work as intended. When I do decide to make a project, I actually enjoy going through the whole process including making the board. It is fun to go from nothing to a working item. I've made some test equipment for my shop that has saved me a few hours time already and paid for themselves in parts, time and effort. Just out of curiosity, anyone else buy the Shacks PCB kits and have any problems with the pens? OR solution? For me, the solution has been ok. MNS "Avery Fineman" wrote in message ... In article , "Ian White, G3SEK" writes: In Europe there's a gadget called a Dalo resist pen which is made specifically for hand-drawing on PCBs. It has a fine fibre tip and very thick, quick-drying ink. It's very expensive for what it is (namely a not very good fibre-tip pen) but with care it can be quite effective. As many people already know, the Staedtler marker pens (waterproof/ wasserfest grade) are excellent for touching-up photo and iron-on resist patterns, but they're not as good as the Dalo for filling large areas. I'll add something from the machine shop that is probably in the UK as well: Marker lacquer used to make marks on metal about to be machined. Over here it is usually a deep blue and is very dilute lacquer, obvious from the acetone odor. Various brands, some are available in red or green (not good colors). Scribes nicely. Brushes well with small brushes available from craft stores. From the drafting department of old: K&E ink pens, the two-part cylindrical, concentric ones. Those will hold dilute lacquers and there is a pen holder that takes the nibs. Must soak them in acetone after using since the capilliary clearance is tiny. With practice those pens can draw straight lines but any dilute lacquer likes to migrate to the straightedge...:-) Office Depot and Office Max chains over here carry the Sanford "Sharpie" pens (permanent marker type) whose ink is ferric chloride resistant. I find it difficult to maintain a fine nib on those for small foil lines and prefer a small brush. Mileage varies. I once tried acetone-diluted liquid rosin as a resist, had mixed results. Nice odor combination while doing it. :-) As always, with any kind of resist, the unetched copper surface must be clean and oxide free, smooth in order to take the resist evenly. Len Anderson retired (from regular hours) electronic engineer person |
#6
![]() |
|||
|
|||
![]()
In article , "Ian White, G3SEK"
writes: In Europe there's a gadget called a Dalo resist pen which is made specifically for hand-drawing on PCBs. It has a fine fibre tip and very thick, quick-drying ink. It's very expensive for what it is (namely a not very good fibre-tip pen) but with care it can be quite effective. As many people already know, the Staedtler marker pens (waterproof/ wasserfest grade) are excellent for touching-up photo and iron-on resist patterns, but they're not as good as the Dalo for filling large areas. I'll add something from the machine shop that is probably in the UK as well: Marker lacquer used to make marks on metal about to be machined. Over here it is usually a deep blue and is very dilute lacquer, obvious from the acetone odor. Various brands, some are available in red or green (not good colors). Scribes nicely. Brushes well with small brushes available from craft stores. From the drafting department of old: K&E ink pens, the two-part cylindrical, concentric ones. Those will hold dilute lacquers and there is a pen holder that takes the nibs. Must soak them in acetone after using since the capilliary clearance is tiny. With practice those pens can draw straight lines but any dilute lacquer likes to migrate to the straightedge...:-) Office Depot and Office Max chains over here carry the Sanford "Sharpie" pens (permanent marker type) whose ink is ferric chloride resistant. I find it difficult to maintain a fine nib on those for small foil lines and prefer a small brush. Mileage varies. I once tried acetone-diluted liquid rosin as a resist, had mixed results. Nice odor combination while doing it. :-) As always, with any kind of resist, the unetched copper surface must be clean and oxide free, smooth in order to take the resist evenly. Len Anderson retired (from regular hours) electronic engineer person |
#7
![]() |
|||
|
|||
![]()
"Ian White, G3SEK" wrote in message ...
Avery Fineman wrote: One thing that all should remember: Electrons don't care about "neat" construction. "Neat" gets something past inspectors, appeals to customers, looks mighty fine and "professional" in photographs. Electrons don't care for any of that. Fields and waves only care about placement of conductors and nearby dielectric material. [...] Right on! But...if one is familiar with RF layout through experience and a "feel" for lead placement and lengths, perf can be used on up to 70 MHz. That is NOT recommended for beginners who have just memorized Ohm's Law. Wish I knew how to pass on that "feel" for RF layout to other people. It's easy to explain to someone why their existing layout doesn't work, but more difficult to make positive recommendations so their next attempt *will* work. I once wrote an article about that for RadCom, which was lifted by the ARRL Handbook and survived for some years as part of the Construction chapter as 'From Schematic to Working Circuit'. That chapter, taken as a whole, is a pretty good basic reference. But in the end, there's no substitute for your own experience. Just build and build and build. Notice what works, and what doesn't... and then the trick is to understand why. For this kind of project, I very often use PCB design software to work up the layout, but don't always etch a board. Just as often, I cut a piece of single-sided board, tape a 1:1 printout of the PCB design onto the board and use it as a drilling template. Then I hand-wire the underside using the layout as a guide. I cheat a bit. Originally an illustrator, I sketch out the foil paths on vellum 1:1, mark the drill holes and use the vellum as a small center-punch guide. The paths are then painted in with lacquer, free-hand, using the vellum as a guide. The lack of those paper-graphics skills is why I use the PCB software. Heck, I even use it for roughing-out stripboard layouts, to try to maximize the use of the strips. In Europe there's a gadget called a Dalo resist pen which is made specifically for hand-drawing on PCBs. It has a fine fibre tip and very thick, quick-drying ink. It's very expensive for what it is (namely a not very good fibre-tip pen) but with care it can be quite effective. As many people already know, the Staedtler marker pens (waterproof/ wasserfest grade) are excellent for touching-up photo and iron-on resist patterns, but they're not as good as the Dalo for filling large areas. Those Dalo pens are nothing but lacquer pens... Sharpies, laundry markers....even other brands of common permanent markers will work..........you can get by cheaper and have a better supply of tip sizes from ultrafine for smt work to xtra large that will cover ground planes nicely. Other permanent markers will also work. Stadtler pens are nice too, dont know their chemical makeup but they are tougher to remove than sharpie lacquer pens with solvents. I do surface mount by hand with a double ended sharpie, one end has the normal fine tip and the other end has the ultrafine tip. I used a piece of clear plastic to layout the patterns for common soic and surface mount resistor capacitor pads and drilled these out with a very fine drill bit used for drilling out small gas appliance orifices, it works great Anyhow.....I have used perfboard for projects before, its quick and if you take your time you can do some really nice work. I have also used g-10 with the copper completely etched off for projects that used larger components where it was easier just to used 18 gauge wire underneath as opposed to ridiculously large traces. For hobbyist purposes perfboard is fine.......its making sure the circuit works and works reliably that counts. |
#8
![]() |
|||
|
|||
![]()
cornytheclown ) writes:
Those Dalo pens are nothing but lacquer pens... Sharpies, laundry markers....even other brands of common permanent markers will work..........you can get by cheaper and have a better supply of tip sizes from ultrafine for smt work to xtra large that will cover ground planes nicely. Other permanent markers will also work. Stadtler pens are nice too, dont know their chemical makeup but they are tougher to remove than sharpie lacquer pens with solvents. There was an article in Ham Radio, in the late eighties or so, when someone wrote about using common pens for etch resist. He mentioned adding some rubbing alcohol to the ink (ie pull open the pen, and put in a bit of it) to make the ink flow better. I know I tried it at the time, and the ink did apply better. I can't remember if I ever etched boards with such a souped up pen. Michael VE2BVW |
#9
![]() |
|||
|
|||
![]()
cornytheclown ) writes:
Those Dalo pens are nothing but lacquer pens... Sharpies, laundry markers....even other brands of common permanent markers will work..........you can get by cheaper and have a better supply of tip sizes from ultrafine for smt work to xtra large that will cover ground planes nicely. Other permanent markers will also work. Stadtler pens are nice too, dont know their chemical makeup but they are tougher to remove than sharpie lacquer pens with solvents. There was an article in Ham Radio, in the late eighties or so, when someone wrote about using common pens for etch resist. He mentioned adding some rubbing alcohol to the ink (ie pull open the pen, and put in a bit of it) to make the ink flow better. I know I tried it at the time, and the ink did apply better. I can't remember if I ever etched boards with such a souped up pen. Michael VE2BVW |
#10
![]() |
|||
|
|||
![]()
"Ian White, G3SEK" wrote in message ...
Avery Fineman wrote: One thing that all should remember: Electrons don't care about "neat" construction. "Neat" gets something past inspectors, appeals to customers, looks mighty fine and "professional" in photographs. Electrons don't care for any of that. Fields and waves only care about placement of conductors and nearby dielectric material. [...] Right on! But...if one is familiar with RF layout through experience and a "feel" for lead placement and lengths, perf can be used on up to 70 MHz. That is NOT recommended for beginners who have just memorized Ohm's Law. Wish I knew how to pass on that "feel" for RF layout to other people. It's easy to explain to someone why their existing layout doesn't work, but more difficult to make positive recommendations so their next attempt *will* work. I once wrote an article about that for RadCom, which was lifted by the ARRL Handbook and survived for some years as part of the Construction chapter as 'From Schematic to Working Circuit'. That chapter, taken as a whole, is a pretty good basic reference. But in the end, there's no substitute for your own experience. Just build and build and build. Notice what works, and what doesn't... and then the trick is to understand why. For this kind of project, I very often use PCB design software to work up the layout, but don't always etch a board. Just as often, I cut a piece of single-sided board, tape a 1:1 printout of the PCB design onto the board and use it as a drilling template. Then I hand-wire the underside using the layout as a guide. I cheat a bit. Originally an illustrator, I sketch out the foil paths on vellum 1:1, mark the drill holes and use the vellum as a small center-punch guide. The paths are then painted in with lacquer, free-hand, using the vellum as a guide. The lack of those paper-graphics skills is why I use the PCB software. Heck, I even use it for roughing-out stripboard layouts, to try to maximize the use of the strips. In Europe there's a gadget called a Dalo resist pen which is made specifically for hand-drawing on PCBs. It has a fine fibre tip and very thick, quick-drying ink. It's very expensive for what it is (namely a not very good fibre-tip pen) but with care it can be quite effective. As many people already know, the Staedtler marker pens (waterproof/ wasserfest grade) are excellent for touching-up photo and iron-on resist patterns, but they're not as good as the Dalo for filling large areas. Those Dalo pens are nothing but lacquer pens... Sharpies, laundry markers....even other brands of common permanent markers will work..........you can get by cheaper and have a better supply of tip sizes from ultrafine for smt work to xtra large that will cover ground planes nicely. Other permanent markers will also work. Stadtler pens are nice too, dont know their chemical makeup but they are tougher to remove than sharpie lacquer pens with solvents. I do surface mount by hand with a double ended sharpie, one end has the normal fine tip and the other end has the ultrafine tip. I used a piece of clear plastic to layout the patterns for common soic and surface mount resistor capacitor pads and drilled these out with a very fine drill bit used for drilling out small gas appliance orifices, it works great Anyhow.....I have used perfboard for projects before, its quick and if you take your time you can do some really nice work. I have also used g-10 with the copper completely etched off for projects that used larger components where it was easier just to used 18 gauge wire underneath as opposed to ridiculously large traces. For hobbyist purposes perfboard is fine.......its making sure the circuit works and works reliably that counts. |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|