https://community.element14.com/technologies/experts/ Have questions for our community members? Ask the experts here!en-USTelligent Community 12https://community.element14.com/technologies/experts/f/forum/56947/ersa-soldering-iron-tip-suddenly-un-tinnable/235707Thu, 21 May 2026 09:26:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:4b90e3db-caac-4b85-9ff2-57e102bc47c6Jan CumpsI have used these products to revive tip wetting issues: They aren't general maintenance solutions. Intended to recover what otherwise would be a throwaway.https://community.element14.com/technologies/experts/f/forum/56954/would-someone-be-interested-to-create-ben-bulsink-s-nfc-game-board/235705Thu, 21 May 2026 09:17:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:c49c458d-f22f-41eb-81ec-1fa29a2548b3jc2048"Does anyone has any idea on it and how to fix this?" Maybe it's trying to protect itself from your coil. I've never worked with NFC, but it seems obvious that there would need to be a way for the chip to protect itself from any items placed into the volume of the operating magnetic field that would, in effect, 'short' the field. A technology used extensively, like this is, needs to be pretty robust and difficult to kill. Imagine the economic mayhem if you could put a card reader out of action with a simple shorted turn. With a low frequency transformer, you'd rely on a fuse to get you out of trouble with a shorted secondary, but here it would either be indirect with a temperature monitor or directly by looking at the current supplied to the TX drive. It's possibly a bit complicated because of the need to power 16 tags simultaneously over a short period with the ISO scheme to enumerate them, so maybe it can't simply be a sensible limit easily within the dissipation limit of the chip - there possibly needs to be a time element to it as well. If the resonance of your makeshift coil with the parallel capacitance on the board is a long way from the operating frequency, it will look like a heavy load to the chip. Just a theory. If you know the parallel capacitance on the board, perhaps you could try the same capacitance alone with the coil, find the resonance, and then adjust the coil so the resonance moves back to 13.56MHz. Then your coil's inductance will match that of the one on the board. Use a good quality SMD cap, similar to the ones on the board (if you use an old leaded part, you'd just be measuring the self resonance of the cap). You could probably get it close enough to function, even if it's not spot on. After all, it can't be too hard a resonance because the signalling sidebands are so far away from the centre (800kHz is it?) and they'll want a reasonable signal level for the RX detection. The grid of coils is an interesting idea, but what would you use to do the multiplexing? Lots of RF relays?https://community.element14.com/technologies/experts/f/forum/56945/help-identify-replacement-for-burnt-out-component/235693Wed, 20 May 2026 22:08:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:ef2673f7-6533-4f2d-92f5-af214e782308stantoUnfortunately I was not in a position to replace those parts within the time and resources available, surprisingly getting hold of parts like this in Norway is not trivial.https://community.element14.com/technologies/experts/f/forum/56965/has-anyone-worked-on-integrating-with-openplotter-for-ais-adsb-marine-ham-band-monitoringWed, 20 May 2026 12:33:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:9b5ccedd-e223-4c18-b6e4-5e541166eb9cKariRI'm interested in replacing my sdr dongles with this kit to integrate AIS ADSB Marine and Ham band monitoring. The capabilities of the kit fit nicely and will allow for simultaneous wideband monitoring over a very wide spectrumhttps://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235668Wed, 20 May 2026 04:47:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:09491d03-25d6-49f7-87c5-0732f333b05aLuka851Thanks once again. I intend to become rf--> nfc engineer, through I am a social, political scientist by education. Finished reading RFID handbook by Klaus Finkenzeller some time ago. Thank you once again and I will try to achieve the good results.https://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235667Wed, 20 May 2026 04:30:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:ec939062-a6fe-4aa0-9ce7-eba2acd3a7a4Luka851Thanks again BigG, I am around Europe but not EU. Ookey, this is good! I appretiate it! It took me time, because I was reading articles from the other guy, to reply with more educated answer..https://community.element14.com/technologies/experts/f/forum/56947/ersa-soldering-iron-tip-suddenly-un-tinnable/235663Tue, 19 May 2026 23:52:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:e105bb8c-45b7-49cd-b9c3-8c462cfad77bshabazI got curious, looks like NASA also adopts IPC along with a 'space standard' modification. The IPC standard recommends brass wool as you say (confirmed by looking at a few videos from IPC trained instructors, they show tools with brass wool, e.g. this one: Master Soldering: IPC-J-STD-001 Soldering Techniques ), and the 'space standard' modification makes the tools recommendations in the appendix of that standard mandatory, because they state "shall be". I looked at these docs: nasa-std-87396b.pdf https://studylib.net/doc/27900669/ipc-j-std-001es-space-application?p=11 (admittedly an older release, it's not possible to view the latest IPC docs without paying for them : (https://community.element14.com/technologies/experts/m/managed-videos/151336Tue, 19 May 2026 23:52:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:9627e412-1faf-4d45-8b3d-628c8ad3adf3shabazProfessional soldering techniques we teach at Circuit Technology Inc. John Gammell, Master IPC Trainer. (919) 552-3434 www.citcuittechnology.comaerospace solderingJ-STD-001John Gammellsolderelectronics engineeringsolder trainingCircuit Technology Incipc j-std-001solderingipc certificationelectronicsipc solderinghttps://community.element14.com/technologies/experts/f/forum/56947/ersa-soldering-iron-tip-suddenly-un-tinnable/235653Tue, 19 May 2026 20:28:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:f7d0d17d-d38d-494c-964c-e8f08d3ab50bJan Cumps[quote userid="8791" url="~/technologies/experts/f/forum/56947/ersa-soldering-iron-tip-suddenly-un-tinnable/235627"]did you read the NASA spec. only sponges [/quote] For earth-bound projects, there's the IPC standard. " IPC advises in the IPC-7711/7721 that especially in lead-free soldering it is better to clean the soldering tip with brass wool / brush (dry cleaning) because this will prevent a temperature shock on your soldering iron tip. However, you can also clean in a wet sponge. " source: https://piektraining.com/en/training-courses/ipc-7711-7721-training/https://community.element14.com/technologies/experts/m/managed-videos/151332Tue, 19 May 2026 16:31:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:fccae556-cb67-40ff-a3e3-376a3f57bdc7BigGEpisode 1943 sent into the channel for review the latest version of NanoVNA. https://www.banggood.com/custlink/m3G9YtcSnb SMA wheels: https://www.pcbway.com/project/shareproject/SMA_Thumbwheel_Wrench_b3dc35b6.html Be a Patron: https://www.patreon....eagle cad8-bit CPUcpm808bit CPUvintage electronicsALTAIRTTL CPU74382s-1008085vintage computings100vintage computerelectronic engineeringcp/meagle pcbALUZetaZeta2circuit designZeta SBCelectronic test equipmentdiy cpuIMSAI 8080IMSAIcpm74181intel 8080electronicselectrical engineeringcpu design743818080pcb designdiy electronicsROMWBWzilog z80https://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235644Tue, 19 May 2026 16:17:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:9e27fcbc-dd84-493e-847f-03b5caaef452shabazForgot to mention the price.. when I purchased, it was 59.68GBP (including taxes and shipping) for the H4 with "test kit" (a few cables and simple open/short/load pieces). I also purchased a couple of "SS405" cables at the same time, that cost an extra £12 GBP.https://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235643Tue, 19 May 2026 16:16:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:de8b9ac9-91cf-4d52-acca-493823ce4f66BigGI feel like a London bus. You've waited for ages to hear back and then you get 2 replies almost one after the other. I purchased my nanoVNA back in 2019 from banggood. The H4 is a step up and has replaced my version. I believe one of the key decision criteria is what max frequency do you want to measure. If it's NFC (13.56MHz) then the nanoVNA is up to the job. If you're looking at much higher frequencies (near the GHz range) then the nanoVNA is probably not good enough. If you're in the EU, then this website (eleshop.eu) is worth buying from as they source orginal equipment and the pricing is pretty good. I see they sell another device " LiteVNA 64 vector network analyser " which is a step up from the nanoVNA and still very reasonably priced. EDIT: As usual, I post then think of other things to add. Here is a review of another "nanoVNA" which is similar to the LiteVNA, in terms of top end scan frequency. The product "NanoVNA-F V3" was from banggood too. At the end of the video "IMSAI Guy" mentions he has a play list covering nanoVNA. Probably worth a watch. www.youtube.com/watchhttps://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235641Tue, 19 May 2026 15:27:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:d4a6532b-84e4-44a5-b6b9-661a2568e46bshabazHi, A VNA is like a flagship instrument for measuring inductances (and more) at RF frequencies, so it's definitely a suitable tool for inductance measurement, but with that caveat that I don't know how far you are prepared to go on that learning curve. Traditionally, only niche industries and RF engineers were prepared to invest that time. The NanoVNA H4 is a very general-purpose, all-round useful VNA, so if you do want a VNA, you could do a lot worse than buy that. I got mine from "Zeenko Store" on AliExpress (I believe that is the official seller). The next question is, will inductance measurement be sufficient to achieve your actual objective, which is to have (I believe) a very long NFC antenna coil that works well along the entire length? The VNA won't measure any electromagnetic fields (well, it might be able to do so but in a more spectrum analyzer-like mode if it can do that, and with different probes). And even if that was successful, the results wouldn't specifically show you what change needs to be made to improve performance, so you could be there tweaking things for days or weeks on end (I'm guessing, no idea, since I've never tried this). In reality, if you really wish to make such an unusual shape antenna work without a lot of trial-and-error, then you'd want to design and simulate it. There is free AN-SOF software, it's got a learning curve too (but hopefully not too much) - I've only used it for a very simple antenna, I've never tried it for NFC. Another option is HFSS, and there is a student license or a trial license, but I don't know the terms/conditions. You could also consider Matlab (see here: https://uk.mathworks.com/matlabcentral/answers/2180231-matlab-nfc-antenna-simulation ) since the "home user" license is affordable (ballpark $100 but I've not checked recently; you'll also need to purchase add-ons called toolboxes, specifically at least the Antenna Toolbox, but more may be needed at a later point as you proceed).As mentioned, all these software options have learning curves.https://community.element14.com/technologies/experts/f/forum/56947/ersa-soldering-iron-tip-suddenly-un-tinnable/235631Tue, 19 May 2026 00:53:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:1f891daa-f428-42d0-97e8-b2b456ac6ddfGough LuiPerhaps you're using the wrong type of flux (too strong, plumbing type) and it's corrosive to the plating on your tip, or the temperature is somehow too high (e.g. temperature feedback thermistor sensor is broken) and the heater is "running away" overheating the tips. - Goughhttps://community.element14.com/technologies/experts/f/forum/56947/ersa-soldering-iron-tip-suddenly-un-tinnable/235627Mon, 18 May 2026 20:21:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:84fc5608-76ec-4252-8d72-c783f2ef95bbphoenixcommproof? did you read the NASA spec. only spongeshttps://community.element14.com/technologies/experts/f/forum/56947/ersa-soldering-iron-tip-suddenly-un-tinnable/235626Mon, 18 May 2026 20:20:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:ab0af3df-a274-40b6-9690-54099494966cphoenixcommSorry I only use Metcal. I have been using them for 25 years; the tips last forever. And on eBay, about $35 or less, NEVER USE BRASS THINGS to clean the tip, only damp sponges, I have a TIP for my Ungar Imperial Iron from high school (8 decades ago)!! still clean and usable.. ~~ Cris H.https://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235624Mon, 18 May 2026 13:35:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:93a4f1c7-94d6-433e-9fe5-0253d4491e6eLuka851Hi Shabaz, I read your articles about Low-cost VNA unboxing, and guide to getting started with VNA. Thanks for writing them! May ask, how is that Low-cost NanoVNA working now in practice? Would you still recommend buying it? and if I may ask, from which platform, which supplier/bradn did you got yours and at what price, becauase when I search on Taobao, Temu, aliExpress there are so many of NanoVNAs of the same brand and still have different prices (different enough to matter - like $50 differences). I want to create 15x15 grid nfc antenna, 15x300mm to make a scrabble game board. instead of making 225 antennas, I will make 15 column and 15 row antenna, and multiplex them to get a exact location of the tile/piece. I am afraid to get a NanoVNA that will not be able to help me there, or do you think it will?https://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235623Mon, 18 May 2026 13:24:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:6da673c6-1930-4b76-ac12-e395b2b247cdLuka851Thank you, I read his article after you commented it, I also read through his other articles, and I have more questions to him. May I ask which NanoVNA do you have, and from which brand/supplier, perhaps at what price as well. I think to buy one on Taobao but the prices are so much different - I don't know what to pick and how to pick a good enough one.https://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235622Mon, 18 May 2026 13:21:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:1d533260-78d3-4751-86bb-b635b48c50f7Luka851Thank you, May I ask which NanoVNA do you have, and from which brand/supplier, perhaps at what price as well. I think to buy one on Taobao but the prices are so much different - I don't know what to pick and how to pick a good enough one.https://community.element14.com/technologies/experts/f/forum/56938/how-to-measure-an-impedance-of-an-nfc-antenna/235621Mon, 18 May 2026 13:19:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:5e710492-9575-45c6-939a-d6b5e4e319abLuka851Thank you, I will look into it