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BboB <electronix@ourd.net>: Jan 27 06:40AM -0500 I know the answer might seem obvious (getting closer, checking connections, etc) but this has me stumped. I recently acquired an older 170 Mhz based Radio Shack wireless mic and receiver for an upcoming event. I got it off of the bay and it was advertised as fully operational, but of course it wasn't. There was no audio upon receipt, and I had to change the mic wire from the electret clip on, to the transmitter. That got it going, but I notice that I have a lot of hiss in the receiver. I've tried moving closer, and I still have the hiss. If I turn off the mic (put on standby), I still have hiss, although a bit weaker as I was obviously getting some hiss from the mic which was expected. However, the hiss that remains stumps me and I shouldn't be getting it. Audio seems to be coming from the receiver fine, but with the amount of hiss, I don't think I'm going to be able to use this for the intended purpose.   I welcome any suggestions here to solve this.   Thank you!

"Peter W." <peterwieck33@gmail.com>: Jan 27 03:49AM -0800 Typically, hiss of the nature you describe - not related to transmission/reception - is due to a failing driver or output device in the audio section. Since it is most likely that these functions are on a single chip, and unless that chip is able to be identified and easily changed, you are right in your diagnosis. As it is obviously defective, you should go ahead and return it if possible.   Without being judgmental, I never purchase anything from 'the bay' on the expectation that it actually works as described. Nor would I sell anything (a very rare occurrence) that I describe as 'working'.   Peter Wieck Melrose Park, PA

Jeff Liebermann <jeffl@cruzio.com>: Jan 27 03:10AM -0800 >https://www.ebay.co.uk/itm/284120960911 (...) >My guess is that all the advertised 'EPOXY' UV glues on ebay and Amazon >are actually Acrylic... anyone know better or for sure? C+   UV curing epoxy is quite real. The problem is I don't know what the eBay vendor is actually selling. I suggest you look at the different curing instructions for UV curing acrylic and epoxy in the article below, and try to determine which one matches the product you purchased.   "UV curing acrylic vs. UV epoxy" <https://www.galindberg.se/blogg/uv-curing-acrylic-vs-uv-epoxy/> Two common types of UV curing (light curing) adhesives are those based on acylate and epoxy. Both are cured using UV or blue light between 365 nm and 405 nm. The difference between them lies in their chemistry. Both the curing process and final properties differ.   Full disclosure: I've worked with UV curable cyanoacrylate adhesive, but not epoxy. -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

Charlie+ <charlie@xxx.net>: Jan 27 06:48AM Anyone happen to really know about this stuff? I baught my example from ebay: https://www.ebay.co.uk/itm/284120960911?ssPageName=STRK%3AMEBIDX%3AIT&var=585619831920&_trksid=p2060353.m2749.l2649   Says its epoxy resin in the ad. and it sets (hot) hard almost instantly with strong UV, quite useful but its not epoxy and doesnt stick like epoxy! Its Acrylic - it even says so on the bottle. Iv used other UV gloops in the past from China and they are softer setting types and definitely Acrylic. I do know that epoxy UV set glue is available industrially, they use UV to kickstart and then continue setting for a time afterwards. However my guess is that these real epoxy types are probably very expensive and not for general use! Asked the seller and got the answer roughly, "well we have no complaints and we sell loads of it" ! My guess is that all the advertised 'EPOXY' UV glues on ebay and Amazon are actually Acrylic... anyone know better or for sure? C+

Mike S <mscir@yahoo.com>: Jan 26 09:15PM -0800 On 1/26/2022 2:37 AM, Chris Jones wrote: > from Silabs that radio amateurs often use as a local oscillator - they > are very simple to use and can produce whatever frequency you need. The > frequency can be programmed with some arduino-type processor etc.   I was thinking the same thing. When I was a tech we used silver, and gold conductive epoxy to attach surface mount components. Once cured it was quite strong.

"ohg...@gmail.com" <ohger1s@gmail.com>: Jan 26 09:47AM -0800 On Wednesday, January 26, 2022 at 9:59:30 AM UTC-5, Peter W. wrote: > Generally, my approach to cracked cases of this nature is to clean thoroughly, add a generous bead of JB-Weld, right up to and including filling the screw holes, allowing it to cure, then drilling out the holes as needed Haven't lost a patient yet. It may not be the prettiest of cures, but it has the overwhelming virtue of working well.   > Peter Wieck > Melrose Park, PA   I'll kluge it together at some point, or retire the meter. Haven't decided.   In the meantime, I checked ebay to see if cases were available, and I found one with ---- a cracked battery door same as mine except both sides are cracked *and* it looks like someone already filled the back case with epoxy for a previous failure. Scroll down the pictures to see the battery door and rear case half. Clearly brittle. Here's a link to the auction and an imgur link of an auction pic that I saved in case anyone sees this years from now after the auction is gone:   https://www.ebay.com/itm/284258608974?hash=item422f22274e:g:3zAAAOSwIshgd~Is   https://i.imgur.com/KOnJnvJ.jpeg   I found a new case on line but its almost as much as the meter cost. <shrug>

Jeff Liebermann <jeffl@cruzio.com>: Jan 26 10:09AM -0800 On Wed, 26 Jan 2022 06:59:27 -0800 (PST), "Peter W."   >Generally, my approach to cracked cases of this nature is to clean thoroughly, add a generous bead of JB-Weld, right up to and including filling the screw holes, allowing it to cure, then drilling out the holes as needed Haven't lost a patient yet. It may not be the prettiest of cures, but it has the overwhelming virtue of working well. >Peter Wieck >Melrose Park, PA   Good idea. I've done case repairs that way. I have to be careful which plastic I try to glue. Some of my epoxies don't want to stick. JB Weld 50139 Plastic Bonder works well enough but takes a full day to properly harden.   What I've been experimenting with is plastic welding. YouTube videos showing how it works with a soldering iron: <https://www.youtube.com/results?search_query=plastic+welding> <https://www.harborfreight.com/80-watt-iron-plastic-welding-kit-60662.html> I didn't do too well because the parts I was trying to weld were too small or thin.   I also tried hot air. Something like these except I made my own tool: <https://www.amazon.com/hot-air-welder/s?k=hot+air+welder> I installed a tiny nozzle on my hot air desoldering station for the welder. I also made a nozzle that heats along a straight seam. I collected some plastic knife shavings from various junk plastic cases found around the shop. No need to color match as all the welding is going to be on the inside of the case. In general, hot air works, but you have protect nearby parts with an aluminum foil heat shield. Also, some practice is helpful.   I have the beginnings of a water gas (HHO) hydrogen generator and torch, which will allow me to make a very narrow hydrogen weld. It's been sitting for about 3 years waiting for me to finish the build. No clue if it will weld nicely (or blow up the shop), but it looks promising. <https://www.youtube.com/results?search_query=HHO+generator>       -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Jan 26 10:22AM -0800 If you have a 3D printer, you could make a replacement battery cover (or have someone make one for you): <https://www.yeggi.com/q/fluke+meter/> <https://cults3d.com/en/tags/fluke%20multimeter> <https://mito3d.com/en/3dmodels/search/fluke/all/all/latest/1> I didn't see anything specific for the 177, but I might have missed it. -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

"ohg...@gmail.com" <ohger1s@gmail.com>: Jan 26 11:46AM -0800 On Wednesday, January 26, 2022 at 1:22:16 PM UTC-5, Jeff Liebermann wrote: > PO Box 272 http://www.LearnByDestroying.com > Ben Lomond CA 95005-0272 > Skype: JeffLiebermann AE6KS 831-336-2558   Good idea Jeff. I searched on the link you provided and found this for a 179, but it looks like the 177 and is most likely the same piece.   https://www.thingiverse.com/thing:3867107

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