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- Fan causing MW RFI - 4 Updates
- Lead-free only? failure mode ? - 5 Updates
- Replacing pump on espresso machine? - 1 Update
| Jeff Layman <JMLayman@invalid.invalid>: Nov 24 12:57PM I have a 6-months old Fantasia ceiling fan (mains powered, with 6-speed reversible dc motor) which is causing a lot of interference on MW. FM is not affected. The interference is there on forward or reverse rotation, worsens as the speed is increased,, and appears on portable as well as mains-powered radios. I can return it to the supplier for replacement or refund, but it is a bit of a rigmarole to remove and refit. All the electronics are sealed in, and the only accessible wiring is to the mains connector. Is there any point in trying some sort of screening or RFI suppression on the mains wiring before I take it down? -- Jeff |
| N_Cook <diverse@tcp.co.uk>: Nov 24 02:01PM On 24/11/2014 12:57, Jeff Layman wrote: > in, and the only accessible wiring is to the mains connector. Is there > any point in trying some sort of screening or RFI suppression on the > mains wiring before I take it down? I find it amazing you can listen to MW/AM in a "modern" house with all that electronic smog and EMI and RFI everywhere |
| Jeff Layman <JMLayman@invalid.invalid>: Nov 24 03:41PM On 24/11/2014 14:01, N_Cook wrote: >> mains wiring before I take it down? > I find it amazing you can listen to MW/AM in a "modern" house with all > that electronic smog and EMI and RFI everywhere Just about everything has a SMPS these days, and often some digital control. Can't say that I've ever had a problem with any of these before. Anyway, is there a more nostalgic way to listen to 60s hits than on a MW portable with a tiny speaker?! -- Jeff |
| N_Cook <diverse@tcp.co.uk>: Nov 24 04:15PM On 24/11/2014 15:41, Jeff Layman wrote: > control. Can't say that I've ever had a problem with any of these before. > Anyway, is there a more nostalgic way to listen to 60s hits than on a MW > portable with a tiny speaker?! How about one of these for nostalgia and low-fi https://www.flickr.com/photos/nhwilber/4701108988/ I repaired one a year or more ago, the owner is supposed to be in the UK and collecting it later this week. Pioneer must be embarassed , its first domestic product. Hardboard deck and no electonics , relied on the old telephone carbon granules principle to feed a speaker, seriously tinny and tiny |
| N_Cook <diverse@tcp.co.uk>: Nov 24 08:32AM I wonder if there is a significance to the sharp deliniation between the mirror finish of the cup part and the maculate finish of the sleeve part. Indicative of differential cold-shocking while cooling ? |
| "Gareth Magennis" <sound.service@btconnect.com>: Nov 24 10:23AM "N_Cook" <diverse@tcp.co.uk> wrote in message news:m4sp8e$ds7$1@dont-email.me... > suggestive of inadequate heating at soldering. > Hopefully a pbf problem on that rear board and not balanced line feed > buffer amp failure , requires removing all the top panel hardware. Was this XLR output being fed to a balanced input (power amp)? If so then you would probably have to have both pins 2 and 3 solder joints fail at the same time to lose signal altogether. If only one failed you would get a 3dB loss of signal. A possible culprit is the Insert jack socket on that output channel, which may have had a dirty normally closed switch contact. Plugging a jack into the nearby line out jack socket could have mechanically jolted it back into life again. Gareth. |
| N_Cook <diverse@tcp.co.uk>: Nov 24 12:11PM On 24/11/2014 10:23, Gareth Magennis wrote: > Gareth. I'd not thought about that, will have to test the bypass breaking force etc on the Inserts. So fixated on trying to prove a PbF touching contact. I'd liked to have seen movement or measured 10 ohm or more , consistently somewhere The 2 break situation is consistent with the following sorry saga, perhaps, but I've concentrated on one "solder" joint, could be one regularly bad and sometimes its mate goes bad. A regular 3db could easily be masked by unmatched sliders or something. Picked up the board this morning and first contact I went to measured 40 to 60 Kohms, tried the rest and .5R or so. Returned to the first and similar .5r now, so has the contact remade or was it oxidised/dirty contact related to my first DVM reading. Felt-tipped the exposed pin/standoffs and flexed the pcb and no shifting seen . Soldered a good contact away from the first suspect joint and fitted a proper XLR into the socket , to make good DVM monitoring points. All measured .5R or so and tended to reduce a bit on heating the pcb to 50 deg C or so and increase to 1.5 ohm or so on freezer spraying the extender parts of the pins. So suspicious but not conclusive . Tried the first contact with passing 3 amp through it , as no active stuff on this board. Dropped just 20mV at the contact. Returning to DVM-R and now it was .1R or so , but increasing to .5R or so on pcb low-level heating. Decided to grind off the cups of the solder joints , bite by bite , to avoid melting solder. Again tried twisting the pcb and deflecting and no movement seen between the brass and the solder . |
| N_Cook <diverse@tcp.co.uk>: Nov 24 01:58PM I desoldered the 2 ground pins. Then tried just finger pressure to pull out the remaining pins. I assume from my previous twisting, or maybe from being bashed in use at some time. The brass pins failed. These are 1.6mm diameter and the pcb holes are for that size. But these Neutrik XLR would seem to be made for old-style hand-wiring then solder, not pcb use. There is a turned recess ring on each pin, down to 1mm diameter, to take a loop or twist of wire before soldering. This recess is the thickness of the pcb. With the pins sheared off now and the remnant stubs still in the pcb , you can see that no solder at all has passed into the .3mm gap around the pins. So in effect the 3 main pins (not the frame ground pin) are only "surface mount" soldered , not through-board soldered, so mechanically weak joints regardless of use of PbF. The shoulder length of the frame ground pin is right for pcb mounting, so are these recessed pins intended for pcb with eyelets , but not used here, or for handwiring? |
| N_Cook <diverse@tcp.co.uk>: Nov 24 02:14PM I cannot find an exact image of them http://www.mondospettacoli.it/shop/index.php?main_page=popup_image&pID=6854 is the nearest long standoffs, is the distant ends of the pins, in that image, eyelets near the ends |
| Amanda Riphnykhazova <licensedtoquill@gmail.com>: Nov 24 12:28AM -0800 WOW! What an amazing point. which i have never heard made before.. I'll bet you are absolutely right. There has to be a reason these machines can't be cleaned properly once they have been so clogged with the limescale There is one proviso however, which is that not all machines have the same material composition to the water chamber. Surely it would be easy to obviate this problem by making the chamber of (eg) stainless steel. One of the currently-acknowledged 'best' machines, the Gaggia Classic uses a curious boiler with an extremely limited life made from aluminium. I have a similar machine called a Baby which I bought second hand which, when enough citric acid had been passed through it to clean off all the limescale, started passing out black dust which seemed to have nothing to do with either limescale or coffee residues. When I dissembled it, I found extensive pitting which was so bad that in places it is 2-3mm deep! No one on the Gaggia forum seemed to have much idea about it save to blame the user for build-up. I can't see it can have been anything other than blackened or oxidised ally? On your other point, there aren't any machines which either make the boiler easy to take out or treat it as a consumable which is going to need replacement every half-decade or so when used in places with a hard water supply? |
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