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Re: Burned up cap
also digikey have some listed but none in stock and saying backorder not possible,any ideas where i can get replacements but possibly 750v versions?,cheers Paul.
By Paul M3VUV · #2206 ·
Re: Burned up cap
well i replaced the cap with 3 mica caps in parelell totaling 218pf,now tho i have no oled display,i have tried good known replacements but nothing,it has the 5v supply going to it,any ideas?.73
By Paul M3VUV · #2205 ·
Re: Burned up cap
Hi, 220pF
By Joaquim Franco · #2204 ·
Re: Burned up cap
Paul, The schematic should be in this GitHub link: https://github.com/Dfinitski/N7DDC-ATU-100-mini-and-extended-boards 73 Evan AC9TU
By Evan Hand · #2203 ·
Re: Burned up cap
Hi, 220pF 73
By Joaquim Franco · #2202 ·
Re: Burned up cap
Paul, As others have recommended I would use the Vishay or Mica Capacitors. I have a Chinese made ATU-100 and run a maximum of 50 watts since I don't trust the quality of the capacitors. Mike N2MS
By Mike N2MS · #2201 ·
Re: cap values
If you don't want to use leaded SM caps, Vishay makes a nice RF cap in 1111 format that just fits. VJ1111D221KXLAT. That's what I used in 'project overkill'. The relays or the pcb traces will arc
By va3rr · #2200 ·
Re: cap values
Surface mount silver mica capacitors exist. You have to step up to the larger 1210 size rather than 0805 to get parts that are rated for 500V; the 0805 ones are only rated for 100V. You're unlikely to
By Shirley Dulcey KE1L · #2199 ·
Re: cap values
its a 220pf 500v silver mica according to the circuit diagram its probably a 220pf ceramic in 0805 size from what I observe of an unbuilt PCB - hth
By mike · #2198 ·
Re: Burned up cap
any idea of the c value?
By paul larner · #2197 ·
Re: Burned up cap
Hi paul go on digikey and get silver mica caps > 500v .. chinese atus use 50v or 100v versions which fail. 73's Jason 9H5BM wrote:
By 9H5BM · #2196 ·
Re: Burned up cap
or where i can find? replacement,nothing on ebay.
By paul larner · #2195 ·
Burned up cap
Hi folks,i was trying my atu-100 on my doublet/ocfd on 80m,it tuned down to about 1.2-1,then after a min of key down it smoked,heres a pic of the cooked cap,dous anyone know the value and type so i
By Paul M3VUV · #2193 ·
Re: ATU-10: an alternative PCB layout?
Hello Yan, do you mean the pad marked in red in the picture below? I don't think that is the fault, it is just where the braid of the cable going to the TRX is grounded. See the pictures below. I was
Re: ATU-10: an alternative PCB layout?
Hi, everyone. I'm BI6MPW from China. I may have found some problems in the process of learning and making atu10. When I studied this version of PCB of zao, I found a doubt that could not be ignored,
By BI6MPW · #2190 ·
Re: ATU-10 kit or build - newdiytech.com website
Hi Stefan, I never tried #43 core on 6m band, so its difficult to say. I measured efficiency of different winding styles end even KN5L method shows rapid drop of efficiency above 30MHz. So even if SWR
By Marek SP9TKW · #2189 ·
Re: New version of control PCB #1KW
Hi! I got the PCB's from JLCPCB yesterday, well done. Programmed right away, tested the drivers passively, with 5V source - they work fine and drive relays much beefier, than the ones I will use in
By Billian Marinov · #2188 ·
Re: ATU-10 kit or build - newdiytech.com website
Hi?Russell and Marek, Yes, I still use my 7-band EFHW 99%, because it's so simple, light and efficient and doesn't need an ATU ;-) For the ones that are not familiar, this is the corresponding
By HB9EAJ · #2187 ·
Re: ATU-10 kit or build - newdiytech.com website
Hi Stephan, I bought ATU-10 to play with EFLW antennas. I find LW useful in small spaces like on holidays or short weekend breaks, putting up 20mtr of wire its sometimes tricky in location where you
By Marek SP9TKW · #2186 ·
Re: ATU-10 kit or build - newdiytech.com website
I have build 49:1 using KN5L method on FT140-43, 2xFT114-43 and FT82A-43 all 28:4 turns. Each one has efficiency over 90%. I rewound all my EFHW QRP transformers and use KN5L method as standard.
By Marek SP9TKW · #2185 ·