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Re: my mic
Hi! Has anyone one tried MEMS microphone like these.. Replacement elements for mobile phones are available quite cheap. Some variants come with in built compressor and noise cancellation. Found a link with Youtube video looks pretty good... Rahul VU3WJM
On Saturday, 4 August, 2018, 8:02:07 AM IST, Jack Purdum via Groups.Io <jjpurdum@...> wrote:
Al Peter, AC8GY, who has a lot more assembly skill than I do, made this mic for me using the stock element and switch: The case is one of those promo pens that had a small LED and battery in it. It really looks nice and is small enough to pack anywhere. Jack, W8TEE
On Friday, August 3, 2018, 7:58:43 PM EDT, hirosmb <hirosmb@...> wrote:
I used the same stereo connector which is bundled with the uBitX kit, mic+ to pin #1 and switch to pin #2.
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Re: 12MHz xtals and QER Filter
Rahul Srivastava
Allison, Here paralleling of cap arose? due to sheer unavailability of good quality caps in pF range in local mkt. I wanted to optimise the filters to best possible extent on local components so that people assembling uBitx in future can do so with whatever in hand or in junk box. It is very helpful to know the impact of such substitutions on filter response. I did try out some 8 and 10MHz filters based on half bridge lattice following the work of DL6ZB , OM Rolf here: ? I found them relatively easy to make, matching non critical and impedance's? easily manageable.? Also found some HC49U 4.43MHz xtals in my old component bin they must be at least 25+ years old from Philips from my post student and struggle days, matched them now? a lot of about 25 xtals and all within 80Hz,? Talk about Quality..!! I made one QER SSB filter its plot is attached. Planning to give a try to some QER filters on 4.915MHz saw a picture on net for an add on board for K2 based on this topology, but I too would prefer xtals in 8-9MHz range with former being more common value.?? As you recommended to avoid ringing sweep rate is kept very slow by keeping the sample rate high on SNA at 1000 samples it sweeps at about 20KHz per minute.? More as experimentation goes on ... TNX and 73 Rahul VU3WJM |
Re: Front Panel Stereo Socket Board Wiring Layout
Ian Reeve
¿ªÔÆÌåÓý
Hi Eddie,? wiring for 4 pin :? pin 1. Mic input,? pin2 PTT,pin3 is put ground and pin 4 is mic ground. So link 3and 4 to earth and pin one is mic and pin 2 is ptt makes sense to keep connections short and screen the mic lead.Hope this helps. Ian M0IDR
Get
From: [email protected] <[email protected]> on behalf of Mvs Sarma <mvssarma@...>
Sent: Saturday, August 4, 2018 4:19:27 AM To: [email protected] Subject: Re: [BITX20] Front Panel Stereo Socket Board Wiring Layout ?
If one has working MICs meant for other rigs that he uses, we can by a similar connector and wire accordingly . It helps sharing the? same mic for ubitx.
regards
sarma
vu3zmv
On Sat, Aug 4, 2018 at 8:08 AM, R. E. Klaus via Groups.Io
<reklaus@...> wrote:
There really is no "standard" for wiring mic connectors. Each brand seems to have their own scheme. Unless you are trying to match a mic from an existing radio, just wire it so it makes sense to you. |
Re: End Fed antennas w/ uBITX
#ubitx
Hi Allison, these 1:49 transformers are just conventional transformers. Would you think that a 1:4 and a 1:9 current (not the voltage ones) transmission line transformers in series to get a ratio 1:36 would be too lossy as I think or may be used? In that case the transmission line of the 1:9 transformer is just 150 ohm which is theoretically too low. Il 04/ago/2018 00:54, "ajparent1/KB1GMX" <kb1gmx@...> ha scritto: The feature that is desired of ferrties and iron power for transformers is coupling as |
Re: any tips for debugging RFI issue?
#ubitx-help
Again, thanks for the explanation.? After adding the air choke and counterpoise (17.5ft -- I'll trim it back tomorrow), the uBITX now behaves properly when keying the mic and transmitting CW!!!
The SWR is a bit higher, though. Also, it has moved a bit toward the Frankenstein's monster end of the aesthetic spectrum. 73 Mike KK7ER |
Re: New antennas group.
Vince Vielhaber
No it wasn't. Arv just created the antenna group today. The loop group you're talking about is different.
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Vince. On 08/03/2018 11:34 PM, Mvs Sarma wrote:
formerly it was --
Michigan VHF Corp. |
Re: New antennas group.
formerly it was Regards MVS Sarma ?vu3zmv On Sat, Aug 4, 2018 at 8:56 AM, Vince Vielhaber <vev@...> wrote: antennas |
Re: New antennas group.
Vince Vielhaber
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On 08/03/2018 10:59 PM, allen west wrote:
What is the exact name of the new antennas group that has been mentioned here? --
Michigan VHF Corp. |
Re: New antennas group.
Regards MVS Sarma ? On Sat, Aug 4, 2018 at 8:29 AM, allen west <kb4ra67@...> wrote: What is the exact name of the new antennas group that has been mentioned here? |
Re: Front Panel Stereo Socket Board Wiring Layout
If one has working MICs meant for other rigs that he uses, we can by a similar connector and wire accordingly . It helps sharing the? same mic for ubitx. regards sarma vu3zmv On Sat, Aug 4, 2018 at 8:08 AM, R. E. Klaus via Groups.Io <reklaus@...> wrote: There really is no "standard" for wiring mic connectors. Each brand seems to have their own scheme. Unless you are trying to match a mic from an existing radio, just wire it so it makes sense to you. |
Re: my mic
Jack Purdum
Al Peter, AC8GY, who has a lot more assembly skill than I do, made this mic for me using the stock element and switch: The case is one of those promo pens that had a small LED and battery in it. It really looks nice and is small enough to pack anywhere. Jack, W8TEE
On Friday, August 3, 2018, 7:58:43 PM EDT, hirosmb <hirosmb@...> wrote:
I used the same stereo connector which is bundled with the uBitX kit, mic+ to pin #1 and switch to pin #2.
|
Re: Managed to pull foil trace off Pop Fix Board (R5)-both sides, K5BCQ kits, Any tricks to get R5 back in place?
#parts
#ubitx-help
First SMD project? OK, then note: to remove a resistor, heat both ends (blob the whole item!) and swipe away from pads to open area (works for smd caps, diodes, transistors too, so long as you don't keep the heat on longer than necessary. ICs really need heat-gun tools.). Repair your faux-pas by finding where those missing pads' traces lead - and to other component pads - and drape an ordinary resistor between. It won't be the prettiest, but it'll work. The component may even stick to the iron tip - if removed from there quickly it most likely will still be OK - a tissue for the job will help you keep track of it.
73, Dex ZL2DEX |
Re: 12MHz xtals and QER Filter
Rahul,
Parallel caps also offer lower ESR best is the values are near the same but it helps. The biggest is crystals ground for series resonance vs parallel.? IT seems to get me a lower ESR and Lm. When I'm doing a lattice or half lattice filter I look for both parallel and series as the? mode difference for a given frequency tends to work in favor for that. My preferred frequency for filters are under 10mhz with 9.6, 9 and 8 being most common but other like 5, 5.0688 have been done.? There is less drift with temperature. I know that from doing a wider than SSB roofing filter at 36mhz,? it had to be or heated! Allison |
Re: ND6T AGC and Click kit wiring notes
Pot, definitely - Rich WB2GXM
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On 8/2/18, Nick VK4PLN <nickpullen@...> wrote:
Hi Again. |
Re: Managed to pull foil trace off Pop Fix Board (R5)-both sides, K5BCQ kits, Any tricks to get R5 back in place?
#parts
#ubitx-help
I have plenty of Pop Fix boards left if you want another 2 kits ......still 2 for $5 mailed. Just no more AGC kits.
73 Kees K5BCQ |
Re: my mic
hirosmb
¿ªÔÆÌåÓýI used the same stereo connector which is bundled with the uBitX kit, mic+ to pin #1 and switch to pin #2.
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