On Thursday, 29 September 2022 at 17:33:01 UTC+1, John Larkin wrote:> On Thu, 29 Sep 2022 11:16:11 -0400, Phil Hobbs > <pcdhSpamM...@electrooptical.net> wrote: > > >John Larkin wrote: > >> On Wed, 28 Sep 2022 17:08:58 GMT, Jan Panteltje > >> <pNaonSt...@yahoo.com> wrote: > >> > >>> On a sunny day (Wed, 28 Sep 2022 07:39:04 -0700) it happened John Larkin > >>> <jla...@highlandSNIPMEtechnology.com> wrote in > >>> <8qm8jh9oaked9p4mh...@4ax.com>: > >>> > >>>> On Wed, 28 Sep 2022 04:56:06 GMT, Jan Panteltje > >>>> <pNaonSt...@yahoo.com> wrote: > >>>> > >>>>> On a sunny day (Tue, 27 Sep 2022 12:44:27 -0700) it happened John Larkin > >>>>> <jlarkin@highland_atwork_technology.com> wrote in > >>>>> <cpi6jhp2rui2013ud...@4ax.com>: > >>>>> > >>>>>> We finally gave up on the dreadful Hammond boxes and custom labels. We > >>>>>> have our own extrusions, blue anodized, and blast all the artwork with > >>>>>> a Boss laser. > >>>>>> > >>>>>> https://www.dropbox.com/sh/cfnhhynh6p3auxf/AACPOsScNGmuH1lAlNCPmSdGa?dl=0 > >>>>>> > >>>>>> This gets us better EMI and some conduction cooling too. Top and > >>>>>> bottom both come off, which is handy when we have parts on both sides > >>>>>> of the board. > >>>>> > >>>>> Makes a bad impression > >>>>> I would like connectors fixed mechanically to the front panel > >>>>> as this way any forces are directly passed to the peeseebee. > >>>> > >>>> Think about the forces when the connector is fastened to the panel. > >>> > >>> Those are controlled by you during assembly, but you never met Big Joe who can turn anything past breakpoint,.. > >> > >> Leave connector nuts loose? > >> > > > >We use a fair number of U.FL to SMA bulkhead cables, which solves both > >problems. > That's expensive and labor intensive and wouldn't work very well in a > small box with lots of connectors. > > http://www.highlandtechnology.com/DSS/T564DS.shtml > > http://www.highlandtechnology.com/DSS/J270DS.shtml > > We are not seeing connectors broken off of PC boards. They make > Corvettes from epoxy-glass. > > We did get one batch of end plates with anodize in the countersunk > holes, in defiance of the notes on the drawing. We'll have to touch up > with a countersink to clean them up, a mild nuisance. I wonder if > there is a kind of flathead screw that has groves or teeth on the > bevels to scrape through the anoddize. I'd google but I don't know > what to call that. > > Maybe our Boss laser could do it, clean out the anodize on the > countersinks.You could consider a selective conductive "alodine" finish in the connector ground areas or even finish the whole box that way. https://en.wikipedia.org/wiki/Chromate_conversion_coating John
new dc/dc converters
Started by ●September 27, 2022
Reply by ●September 29, 20222022-09-29
Reply by ●September 29, 20222022-09-29
John Larkin wrote:> On Thu, 29 Sep 2022 11:16:11 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> John Larkin wrote: >>> On Wed, 28 Sep 2022 17:08:58 GMT, Jan Panteltje >>> <pNaonStpealmtje@yahoo.com> wrote: >>> >>>> On a sunny day (Wed, 28 Sep 2022 07:39:04 -0700) it happened John Larkin >>>> <jlarkin@highlandSNIPMEtechnology.com> wrote in >>>> <8qm8jh9oaked9p4mh4jbumqdd0ict06n5j@4ax.com>: >>>> >>>>> On Wed, 28 Sep 2022 04:56:06 GMT, Jan Panteltje >>>>> <pNaonStpealmtje@yahoo.com> wrote: >>>>> >>>>>> On a sunny day (Tue, 27 Sep 2022 12:44:27 -0700) it happened John Larkin >>>>>> <jlarkin@highland_atwork_technology.com> wrote in >>>>>> <cpi6jhp2rui2013ud74ih85ncn8cjmhkn8@4ax.com>: >>>>>> >>>>>>> We finally gave up on the dreadful Hammond boxes and custom labels. We >>>>>>> have our own extrusions, blue anodized, and blast all the artwork with >>>>>>> a Boss laser. >>>>>>> >>>>>>> https://www.dropbox.com/sh/cfnhhynh6p3auxf/AACPOsScNGmuH1lAlNCPmSdGa?dl=0 >>>>>>> >>>>>>> This gets us better EMI and some conduction cooling too. Top and >>>>>>> bottom both come off, which is handy when we have parts on both sides >>>>>>> of the board. >>>>>> >>>>>> Makes a bad impression >>>>>> I would like connectors fixed mechanically to the front panel >>>>>> as this way any forces are directly passed to the peeseebee. >>>>> >>>>> Think about the forces when the connector is fastened to the panel. >>>> >>>> Those are controlled by you during assembly, but you never met Big Joe who can turn anything past breakpoint,.. >>> >>> Leave connector nuts loose? >>> >> >> We use a fair number of U.FL to SMA bulkhead cables, which solves both >> problems. > > That's expensive and labor intensive and wouldn't work very well in a > small box with lots of connectors. > > http://www.highlandtechnology.com/DSS/T564DS.shtml > > http://www.highlandtechnology.com/DSS/J270DS.shtml > > We are not seeing connectors broken off of PC boards. They make > Corvettes from epoxy-glass. > > We did get one batch of end plates with anodize in the countersunk > holes, in defiance of the notes on the drawing. We'll have to touch up > with a countersink to clean them up, a mild nuisance. I wonder if > there is a kind of flathead screw that has groves or teeth on the > bevels to scrape through the anoddize. I'd google but I don't know > what to call that. > > Maybe our Boss laser could do it, clean out the anodize on the > countersinks. >Yeah, we normally have one to three connectors. We really like U.FLs--they have a nice positive snap action, have gold contacts, cost 20 cents, are the size of a SOT23, work up to 6 GHz or so, and have next to no capacitance. Other than that, they stink.k Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●September 29, 20222022-09-29
John Walliker wrote:> On Thursday, 29 September 2022 at 17:33:01 UTC+1, John Larkin wrote: >> On Thu, 29 Sep 2022 11:16:11 -0400, Phil Hobbs >> <pcdhSpamM...@electrooptical.net> wrote: >> >>> John Larkin wrote: >>>> On Wed, 28 Sep 2022 17:08:58 GMT, Jan Panteltje >>>> <pNaonSt...@yahoo.com> wrote: >>>> >>>>> On a sunny day (Wed, 28 Sep 2022 07:39:04 -0700) it happened John Larkin >>>>> <jla...@highlandSNIPMEtechnology.com> wrote in >>>>> <8qm8jh9oaked9p4mh...@4ax.com>: >>>>> >>>>>> On Wed, 28 Sep 2022 04:56:06 GMT, Jan Panteltje >>>>>> <pNaonSt...@yahoo.com> wrote: >>>>>> >>>>>>> On a sunny day (Tue, 27 Sep 2022 12:44:27 -0700) it happened John Larkin >>>>>>> <jlarkin@highland_atwork_technology.com> wrote in >>>>>>> <cpi6jhp2rui2013ud...@4ax.com>: >>>>>>> >>>>>>>> We finally gave up on the dreadful Hammond boxes and custom labels. We >>>>>>>> have our own extrusions, blue anodized, and blast all the artwork with >>>>>>>> a Boss laser. >>>>>>>> >>>>>>>> https://www.dropbox.com/sh/cfnhhynh6p3auxf/AACPOsScNGmuH1lAlNCPmSdGa?dl=0 >>>>>>>> >>>>>>>> This gets us better EMI and some conduction cooling too. Top and >>>>>>>> bottom both come off, which is handy when we have parts on both sides >>>>>>>> of the board. >>>>>>> >>>>>>> Makes a bad impression >>>>>>> I would like connectors fixed mechanically to the front panel >>>>>>> as this way any forces are directly passed to the peeseebee. >>>>>> >>>>>> Think about the forces when the connector is fastened to the panel. >>>>> >>>>> Those are controlled by you during assembly, but you never met Big Joe who can turn anything past breakpoint,.. >>>> >>>> Leave connector nuts loose? >>>> >>> >>> We use a fair number of U.FL to SMA bulkhead cables, which solves both >>> problems. >> That's expensive and labor intensive and wouldn't work very well in a >> small box with lots of connectors. >> >> http://www.highlandtechnology.com/DSS/T564DS.shtml >> >> http://www.highlandtechnology.com/DSS/J270DS.shtml >> >> We are not seeing connectors broken off of PC boards. They make >> Corvettes from epoxy-glass. >> >> We did get one batch of end plates with anodize in the countersunk >> holes, in defiance of the notes on the drawing. We'll have to touch up >> with a countersink to clean them up, a mild nuisance. I wonder if >> there is a kind of flathead screw that has groves or teeth on the >> bevels to scrape through the anoddize. I'd google but I don't know >> what to call that. >> >> Maybe our Boss laser could do it, clean out the anodize on the >> countersinks. > > You could consider a selective conductive "alodine" finish in the connector ground areas > or even finish the whole box that way. > > https://en.wikipedia.org/wiki/Chromate_conversion_coating > > John >The hexavalent chrome stuff is very good, but has just about been regulated out of existence. The Cr+4 stuff sucks. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●September 29, 20222022-09-29
Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote: <snip>> Today was interesting, I killed my Chinese satellite receiver box few days > ago in the storm > likely did draw too much power when I moved the dish against the storm we had. > had replaced the original current limited 12 V wallwart with a more powerful > one.. my fault... > It would still move the dish but always to the wrong angle.. > Dish motor on PC sat card OK,, So dish positioner OK. > Bought the thing for about 30$ or so on ebay years ago, 1080 progressive HD, > 900 free TV channels, many satellites.. > Lots like these now for double that price locally... > Anyways opened it, and could not find any defective parts > Very nice multilayer board, very dense, tuner, several switchmode converters... > no partnumers readable.. > Almost gave up.. what could it be? lots of work to enter all my satellites and > stations in a new one.. > then I had an idea, nothing to lose... switched from manual angle definitions > to USALS > and low and behold, now I have even more stations > Probably a bit flipped in the firmware, but in USALS it calculates position > from your current (GPS) location each time you select a sat, > > And look how nice it is made,: > http://panteltje.com/pub/hd_sat_reciever_front_IXIMG_0862.JPG > http://panteltje.com/pub/hd_sat_receiver_backpanel_IXIMG_0863.JPG > http://panteltje.com/pub/hd_sat_receiver_backpanel_IXIMG_0864.JPG > http://panteltje.com/pub/hd_sat_receiver_inside_IXIMG_0865.JPG > that is a 500 MHz processor under that little heatsink (ball grid array) > The buttons and display are on a separate PCBs conencted with flex cable. > You can open it by removing 2 screws in the back > thin metal housing just slides backward... > nice cinch connectors screwed against the back > LNB input fixed to tuner module that is fixed to the PCB can take a hit > > and 30$ !!!! > There is a LOT to learn from this, I had it all apart and was amazed by the PCB layout> > My hat off to the designer of that box. > > Value for money .. value for many... > many versions :-) > https://www.ebay.com/itm/354190172519"Value for money .. value for many..." says it all. Beings the OP's "look at my cobbled together thing" serves as this thread's theme, here's another peek at my own cobbled contraption: <https://crcomp.net/mp3mod/index.php> My webpage needs an update because this guy: <https://www.ebay.com/itm/304571755908> recently replaced the cheap mp3 player. The new board costs only US$3.95 and it runs circles around the old player. You can read about all of the functionality packed into one proprietary chip on my new board. For my purposes - outdoor cycle spins and dog walks - only the 3.5mm output's necessary. Connected to a Sony Walkman MJR-J10, because they reliably stay in place. A few sad old dogs whined about corded earbuds and mp3 players the last time a link to my gizmo was posted. Nonetheless, in the end, my gadget proves out as the best solution for my needs. Danke, -- Don, KB7RPU, https://www.qsl.net/kb7rpu There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.
Reply by ●September 29, 20222022-09-29
On Thu, 29 Sep 2022 13:07:25 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>John Larkin wrote: >> On Thu, 29 Sep 2022 11:16:11 -0400, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> John Larkin wrote: >>>> On Wed, 28 Sep 2022 17:08:58 GMT, Jan Panteltje >>>> <pNaonStpealmtje@yahoo.com> wrote: >>>> >>>>> On a sunny day (Wed, 28 Sep 2022 07:39:04 -0700) it happened John Larkin >>>>> <jlarkin@highlandSNIPMEtechnology.com> wrote in >>>>> <8qm8jh9oaked9p4mh4jbumqdd0ict06n5j@4ax.com>: >>>>> >>>>>> On Wed, 28 Sep 2022 04:56:06 GMT, Jan Panteltje >>>>>> <pNaonStpealmtje@yahoo.com> wrote: >>>>>> >>>>>>> On a sunny day (Tue, 27 Sep 2022 12:44:27 -0700) it happened John Larkin >>>>>>> <jlarkin@highland_atwork_technology.com> wrote in >>>>>>> <cpi6jhp2rui2013ud74ih85ncn8cjmhkn8@4ax.com>: >>>>>>> >>>>>>>> We finally gave up on the dreadful Hammond boxes and custom labels. We >>>>>>>> have our own extrusions, blue anodized, and blast all the artwork with >>>>>>>> a Boss laser. >>>>>>>> >>>>>>>> https://www.dropbox.com/sh/cfnhhynh6p3auxf/AACPOsScNGmuH1lAlNCPmSdGa?dl=0 >>>>>>>> >>>>>>>> This gets us better EMI and some conduction cooling too. Top and >>>>>>>> bottom both come off, which is handy when we have parts on both sides >>>>>>>> of the board. >>>>>>> >>>>>>> Makes a bad impression >>>>>>> I would like connectors fixed mechanically to the front panel >>>>>>> as this way any forces are directly passed to the peeseebee. >>>>>> >>>>>> Think about the forces when the connector is fastened to the panel. >>>>> >>>>> Those are controlled by you during assembly, but you never met Big Joe who can turn anything past breakpoint,.. >>>> >>>> Leave connector nuts loose? >>>> >>> >>> We use a fair number of U.FL to SMA bulkhead cables, which solves both >>> problems. >> >> That's expensive and labor intensive and wouldn't work very well in a >> small box with lots of connectors. >> >> http://www.highlandtechnology.com/DSS/T564DS.shtml >> >> http://www.highlandtechnology.com/DSS/J270DS.shtml >> >> We are not seeing connectors broken off of PC boards. They make >> Corvettes from epoxy-glass. >> >> We did get one batch of end plates with anodize in the countersunk >> holes, in defiance of the notes on the drawing. We'll have to touch up >> with a countersink to clean them up, a mild nuisance. I wonder if >> there is a kind of flathead screw that has groves or teeth on the >> bevels to scrape through the anoddize. I'd google but I don't know >> what to call that. >> >> Maybe our Boss laser could do it, clean out the anodize on the >> countersinks. >> > >Yeah, we normally have one to three connectors. We really like >U.FLs--they have a nice positive snap action, have gold contacts, cost >20 cents, are the size of a SOT23, work up to 6 GHz or so, and have next >to no capacitance. Other than that, they stink.k > >Cheers > >Phil HobbsThey are hard to mate and un-mate. Transmission-line transformer, stock cable assembly: https://www.dropbox.com/s/5o6mf5x94n1e08a/Z412_X.JPG?raw=1 https://www.dropbox.com/s/kc217v0lfqaa48u/Pot_Core_TXline.JPG?raw=1 https://www.dropbox.com/s/zpu6wpli7pvwuih/TX_1.jpg?raw=1
Reply by ●September 29, 20222022-09-29
On 29/9/22 11:55, Anthony William Sloman wrote:> On Thursday, September 29, 2022 at 8:05:37 AM UTC+10, John Larkin wrote: >> On Thu, 29 Sep 2022 07:00:50 +1000, Clifford Heath <no_...@please.net> wrote: >>> On 29/9/22 02:19, Don wrote: >> >>>> On the other hand, companies who manufacture consumer products must put >>>> more thought into design language: <https://paia.com/> >>> >>> That's not just consumer - it's music production. Those folk are true >>> aesthetes. Musicians believe that beautiful instruments enable them to >>> make more beautiful music, and I think they're right. >>> >> It's a fact that beautiful schematics and pcb's work better than ugly ones. > > But beauty is in the eye of the beholder. > > Some people don't think about what they are seeing, and aesthetic appreciation isn't a rational process. If a schematic or a pcb just looks like one that worked well in the past, you are going to like it better than one that looks like something that didn't. As "facts" go, this has to be one of the less useful ones. >Beauty might be in the eye of the beholder, but if you lack any aesthetic sense, ugliness is a knife in your back.
Reply by ●September 29, 20222022-09-29
On Fri, 30 Sep 2022 08:26:55 +1000, Clifford Heath <no_spam@please.net> wrote:>On 29/9/22 11:55, Anthony William Sloman wrote: >> On Thursday, September 29, 2022 at 8:05:37 AM UTC+10, John Larkin wrote: >>> On Thu, 29 Sep 2022 07:00:50 +1000, Clifford Heath <no_...@please.net> wrote: >>>> On 29/9/22 02:19, Don wrote: >>> >>>>> On the other hand, companies who manufacture consumer products must put >>>>> more thought into design language: <https://paia.com/> >>>> >>>> That's not just consumer - it's music production. Those folk are true >>>> aesthetes. Musicians believe that beautiful instruments enable them to >>>> make more beautiful music, and I think they're right. >>>> >>> It's a fact that beautiful schematics and pcb's work better than ugly ones. >> >> But beauty is in the eye of the beholder. >> >> Some people don't think about what they are seeing, and aesthetic appreciation isn't a rational process. If a schematic or a pcb just looks like one that worked well in the past, you are going to like it better than one that looks like something that didn't. As "facts" go, this has to be one of the less useful ones. >> > >Beauty might be in the eye of the beholder, but if you lack any >aesthetic sense, ugliness is a knife in your back.Beautiful schematics and boards work better for a couple of reasons. One, they have had more time being beautified and looked at and thought about. Two, they are designed by people who really care about details.
Reply by ●September 30, 20222022-09-30
On Friday, September 30, 2022 at 8:47:13 AM UTC+10, John Larkin wrote:> On Fri, 30 Sep 2022 08:26:55 +1000, Clifford Heath <no_...@please.net> wrote: > >On 29/9/22 11:55, Anthony William Sloman wrote: > >> On Thursday, September 29, 2022 at 8:05:37 AM UTC+10, John Larkin wrote: > >>> On Thu, 29 Sep 2022 07:00:50 +1000, Clifford Heath <no_...@please.net> wrote: > >>>> On 29/9/22 02:19, Don wrote: > >>> > >>>>> On the other hand, companies who manufacture consumer products must put > >>>>> more thought into design language: <https://paia.com/> > >>>> > >>>> That's not just consumer - it's music production. Those folk are true > >>>> aesthetes. Musicians believe that beautiful instruments enable them to > >>>> make more beautiful music, and I think they're right. > >>>> > >>> It's a fact that beautiful schematics and pcb's work better than ugly ones. > >> > >> But beauty is in the eye of the beholder. > >> > >> Some people don't think about what they are seeing, and aesthetic appreciation isn't a rational process. If a schematic or a pcb just looks like one that worked well in the past, you are going to like it better than one that looks like something that didn't. As "facts" go, this has to be one of the less useful ones. > > > >Beauty might be in the eye of the beholder, but if you lack any > >aesthetic sense, ugliness is a knife in your back. > > Beautiful schematics and boards work better for a couple of reasons. > One, they have had more time being beautified and looked at and > thought about.This helps if the person who did the beautification knew what they were doing. Bringing the board proportions closer to the gold mean won't make the circuit work any better> Two, they are designed by people who really care about details.Caring about details isn't getting the fundamentals right. John Larkin doesn't care about design details enough to have any enthusiasm for designing his own special purpose transformers to have exactly the right performance for a particular circuit. Caring about the proportions of the printed circuit board is a less profitable use of his time. -- Bill Sloman, Sydney
Reply by ●September 30, 20222022-09-30
On a sunny day (Thu, 29 Sep 2022 18:08:14 -0000 (UTC)) it happened "Don" <g@crcomp.net> wrote in <20220929a@crcomp.net>:>Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote: >> https://www.ebay.com/itm/354190172519 > >"Value for money .. value for many..." says it all.>Beings the OP's "look at my cobbled together thing" serves as this >thread's theme, here's another peek at my own cobbled contraption: ><https://crcomp.net/mp3mod/index.php>Ha! I have several of those ! Bought many years ago from ebay... My mp3 player however is a Creative Muvo, 10 hours on an eneloop AAA>My webpage needs an update because this guy: ><https://www.ebay.com/itm/304571755908> recently replaced the cheap mp3 >player.That one is new to me... My creative muvo has been working now for almost 13 years...? http://panteltje.com/pub/muvo_1_img_1638.jpg http://panteltje.com/pub/muvo_2_img_1639.jpg http://panteltje.com/pub/muvo_3_img_1640.jpg No idea what I payed for it, bought locally in a store, love at first sight. Also have a credit card size mp3 / video player from ebay and little credit card size FM radios Some came 3 for a few dollars... Al works.>The new board costs only US$3.95 and it runs circles around the >old player. You can read about all of the functionality packed into one >proprietary chip on my new board. > For my purposes - outdoor cycle spins and dog walks - only the 3.5mm >output's necessary. Connected to a Sony Walkman MJR-J10, because they >reliably stay in place. > A few sad old dogs whined about corded earbuds and mp3 players the >last time a link to my gizmo was posted. Nonetheless, in the end, my >gadget proves out as the best solution for my needs. > >Danke, > >-- >Don, KB7RPU, https://www.qsl.net/kb7rpuInteresting links My wall clock: http://panteltje.com/panteltje/raspberry_pi_FDS132_matrix_display_driver/index.html
Reply by ●September 30, 20222022-09-30
John Larkin wrote:> On Thu, 29 Sep 2022 13:07:25 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> John Larkin wrote: >>> On Thu, 29 Sep 2022 11:16:11 -0400, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> John Larkin wrote: >>>>> On Wed, 28 Sep 2022 17:08:58 GMT, Jan Panteltje >>>>> <pNaonStpealmtje@yahoo.com> wrote: >>>>> >>>>>> On a sunny day (Wed, 28 Sep 2022 07:39:04 -0700) it happened John Larkin >>>>>> <jlarkin@highlandSNIPMEtechnology.com> wrote in >>>>>> <8qm8jh9oaked9p4mh4jbumqdd0ict06n5j@4ax.com>: >>>>>> >>>>>>> On Wed, 28 Sep 2022 04:56:06 GMT, Jan Panteltje >>>>>>> <pNaonStpealmtje@yahoo.com> wrote: >>>>>>> >>>>>>>> On a sunny day (Tue, 27 Sep 2022 12:44:27 -0700) it happened John Larkin >>>>>>>> <jlarkin@highland_atwork_technology.com> wrote in >>>>>>>> <cpi6jhp2rui2013ud74ih85ncn8cjmhkn8@4ax.com>: >>>>>>>> >>>>>>>>> We finally gave up on the dreadful Hammond boxes and custom labels. We >>>>>>>>> have our own extrusions, blue anodized, and blast all the artwork with >>>>>>>>> a Boss laser. >>>>>>>>> >>>>>>>>> https://www.dropbox.com/sh/cfnhhynh6p3auxf/AACPOsScNGmuH1lAlNCPmSdGa?dl=0 >>>>>>>>> >>>>>>>>> This gets us better EMI and some conduction cooling too. Top and >>>>>>>>> bottom both come off, which is handy when we have parts on both sides >>>>>>>>> of the board. >>>>>>>> >>>>>>>> Makes a bad impression >>>>>>>> I would like connectors fixed mechanically to the front panel >>>>>>>> as this way any forces are directly passed to the peeseebee. >>>>>>> >>>>>>> Think about the forces when the connector is fastened to the panel. >>>>>> >>>>>> Those are controlled by you during assembly, but you never met Big Joe who can turn anything past breakpoint,.. >>>>> >>>>> Leave connector nuts loose? >>>>> >>>> >>>> We use a fair number of U.FL to SMA bulkhead cables, which solves both >>>> problems. >>> >>> That's expensive and labor intensive and wouldn't work very well in a >>> small box with lots of connectors. >>> >>> http://www.highlandtechnology.com/DSS/T564DS.shtml >>> >>> http://www.highlandtechnology.com/DSS/J270DS.shtml >>> >>> We are not seeing connectors broken off of PC boards. They make >>> Corvettes from epoxy-glass. >>> >>> We did get one batch of end plates with anodize in the countersunk >>> holes, in defiance of the notes on the drawing. We'll have to touch up >>> with a countersink to clean them up, a mild nuisance. I wonder if >>> there is a kind of flathead screw that has groves or teeth on the >>> bevels to scrape through the anoddize. I'd google but I don't know >>> what to call that. >>> >>> Maybe our Boss laser could do it, clean out the anodize on the >>> countersinks. >>> >> >> Yeah, we normally have one to three connectors. We really like >> U.FLs--they have a nice positive snap action, have gold contacts, cost >> 20 cents, are the size of a SOT23, work up to 6 GHz or so, and have next >> to no capacitance. Other than that, they stink. >>> They are hard to mate and un-mate.Mating is easy. Unmating needs a quarter-twist of a small screwdriver under the panhandle (where the cable attaches). One of their principal virtues is that you can sprinkle them as test points, which gets rid of the usual scope probe problems with pickup and ground inductance. They don't have to be populated in the production boards, and the footprints are small enough to ignore (usually).> Transmission-line transformer, stock cable assembly: > > https://www.dropbox.com/s/5o6mf5x94n1e08a/Z412_X.JPG?raw=1 > > https://www.dropbox.com/s/kc217v0lfqaa48u/Pot_Core_TXline.JPG?raw=1 > > https://www.dropbox.com/s/zpu6wpli7pvwuih/TX_1.jpg?raw=1 >Yeah, that's a cute hack I've been meaning tor try out. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
