Re: Relay Board version 5 and BPF switching
#bpf
Hi Colin
Please see? , I have just added this information to the page.?
73 Hans G0UPL
On Fri, Jan 19, 2018 at 3:38 AM, Colin Buckup via Groups.Io <rotbaron77@...> wrote: Hello gang,
Continuing my quest to complete the multi-band 5W Tx/Rx project, I just got my latest batch of kits in the mail. Included was the Relay Board revision 5 which now has as "normal" the option of always?having 1 LPF in the circuit. That works great for the TX side (LPF's). But not so for the RX side since you can't serialize BPF's...
Canvassing the web site and the previous discussions it seems that the Assembly Instructions for Revision 5, although making reference to the jumper configuration when using the relay board for BPF switching, never show the correct jumper setting for it and leave it open as? "published in another document".
I could not find this document anywhere on the site... did I miss anything?
Looking at the circuit diagram it seems that if I want to use the 5 relays to switch 5 different BPF's, the output side of position 1 is ALWAYS connected to the center pin of the SMA coax connector. That would mean that if I configure the jumpers as NOT always having pos 1 in series and would as an example select any other position (say relay 4) and since the relay in position 1 is not energized (grounding the output of the BPF) that this would pull the SMA center pin to ground.
Do I need to perform a slight surgery on the board to prevent that? Anyone with previous experience in this? Rev 4 was easier since the RFin and RFout lines were always clear of the non-energized relays.
Hans, any ideas? does that jumper config doc exists somewhere and did I miss it?
Thanks to all
73
Colin - N5GG
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Relay Board version 5 and BPF switching
#bpf
Hello gang,
Continuing my quest to complete the multi-band 5W Tx/Rx project, I just got my latest batch of kits in the mail. Included was the Relay Board revision 5 which now has as "normal" the option of always?having 1 LPF in the circuit. That works great for the TX side (LPF's). But not so for the RX side since you can't serialize BPF's...
Canvassing the web site and the previous discussions it seems that the Assembly Instructions for Revision 5, although making reference to the jumper configuration when using the relay board for BPF switching, never show the correct jumper setting for it and leave it open as? "published in another document".
I could not find this document anywhere on the site... did I miss anything?
Looking at the circuit diagram it seems that if I want to use the 5 relays to switch 5 different BPF's, the output side of position 1 is ALWAYS connected to the center pin of the SMA coax connector. That would mean that if I configure the jumpers as NOT always having pos 1 in series and would as an example select any other position (say relay 4) and since the relay in position 1 is not energized (grounding the output of the BPF) that this would pull the SMA center pin to ground.
Do I need to perform a slight surgery on the board to prevent that? Anyone with previous experience in this? Rev 4 was easier since the RFin and RFout lines were always clear of the non-energized relays.
Hans, any ideas? does that jumper config doc exists somewhere and did I miss it?
Thanks to all
73
Colin - N5GG
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Re: Antenna Analyzer using the QRP-LABS Arduino shield
I changed the circuit and program to support switched lowpass filters.? The program is written to support 3 filters.? I uploaded another circuit diagram.? The new circuit could also be used without relay switched filters if one wished, so I think this is the better way to go.
I don't expect to be making many more changes
Ron? K1URC
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Re: QCX- No xmit or receive.
Hi Glen,
On 18/01/2018 17:19, Glen Sr wrote:
Could
Q5 be open?
Any thing is possible.
Taking a clue from your subject field. It will not prevent
Transmit function though.
There are no Transmit / Receive relays or PIN Diode switching in
this design.
Look at the schematic and Han's write up of how that stage works
in section 5.8
the transmit PA devices are permanently connected to the LPF and
Antenna jack.
Q5 provides couples the RX circuitry to the antenna jack during RX
& providing isolation to prevent damage to the switcher /
detector IC during TX cycle.
If Q5 was open I would expect the unit should still transmit.
Can
I jumper Q5 to see if I can hear a signal without further damage?
Glen N8WE
If you suspect Q5 pull it from the board.
it's a N-channel FET, there is a bit of an
knack to measuring FET's because they are a high input impedance
device.
Iif you read the junctions in any old order
you can land on the combination that turns the gate on, then you
move the test leads to source & drain. And you then convince
yourself it's faulty when it's not....
Ideally if you have one of those cheep Chinese
component testers use that, if you use a meter then perhaps Google
is your best friend for tips before you try yours.
If Q5 is not faulty, logical fault finding is
the best approach.
Re-read the assembly manual, even the sections
printed in red.
QCX home page, has a common issues section.
QCX Mods page, has MOD's and component changes
you need to be aware of, depending on your kit S No#
Has the unit ever worked correctly then
failed, or is it a new build that's never worked?
Unit aligned correctly, through each section,
strange behaviour or anything that you were not sure about?
(motorboating, moving bar graphs when you were not adjusting
anything, warm smells / magic smoke?)
Compared your voltages to typical ones given
in the troubleshooting section of the manual?
let us know what you find.
If there is nothing conclusive, a good photo
image of the component side & solder side of the PCB with the
LCD removed and we can look at anything with a fresh pair of
eye's.
What test equipment have you access to?
Regards Alan
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Could Q5 be open? Can I jumper Q5 to see if I can hear a signal without further damage? Glen N8WE
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Re: QCX 80 Transceiver - Connection for a Straight Key
Hans I have fitted stereo jacks to the keys and they do work in the stereo socket. I confirm that?the green wire was cut internally in the Palm Radio PPK straight key to avoid shorting between ring and ground (this mod is required for certain other rigs such as K3
Robin
G4DNP
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I've been running my 40m QCX on WSPR for the past few days and thought I'd comment on the start-up behavior I'm getting with my QLG1 GPS module.
My QLG1 when it's first powered up can take about 30-40 seconds before I start getting a 1 PPS signal. This seems like it would be normal to expect while it's gathering satellite data.
When the QCX starts up in WSPR mode it 'settles down' in about 5-10 seconds with the clock showing 00:00:xx and the transmit interval for the next programmed start time. Since the QCX has not received a time signal from the QLG1 this would be expected behavior.
OK, went the start time is encountered, the QCX will transmit, but chances are good it's not going to be anywhere near the normal WSPR even-minute time. After this transmit interval it looks like it performs a quick frequency check and we start seeing the correct GPS time and from here on normal WSPR operation is assured.
The workaround I've been using is to get the QCX into Alignment, menu #8.3 to monitor GPS data and/or menu #8.11 or #8.12. Once the 1PPS signal shows on the QGL1 these items will start to yield results, and upon exiting out of the menu mode I'll see valid time and transmit start times. BTW, in my case GPS data many times just shows 'T' and 'S' values at least at this start up time. I never get a 3D indication even when it's connected to my U3S.
If all of this is considered pretty normal, it would be nice if a future version of firmware would perhaps check for GPS after a short time, maybe after a minute of operation. I understand operation without GPS is part of normal operation and for a CW beacon there's really no need for it.
Cheers!
--Al
WD4AH
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a while ago someone asked how others were connecting the GPS unit to the QCX.
I have just done mine and it seems to work just fine. I bought two TRRS jacks and a TRSS to TRSS cable from Amazon. (The 3.5 mm 4 conductor) and it works great.
because there is +5V and gnd on the connector remember to power down first.
I have a 3 foot cable and it was plug and play. I used RTV to mount the Jack to the GPS board and panel mounted the QCX end. I was going to mount in the case with an opening for antenna but I needed a way to remove
it for CW use.
It works FB on CW and WSPR.
73
Barry
NF1O
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Re: Power lag issue on QCX
#qcx
On key down at low supply voltages there is a lag before reaching the final power. Example: For a 11.5V supply it starts at 1W, and there is a delay of several seconds before a fairly rapid increase, reaching the final value of 2.3W.
Euan, You may like to read Hans' guess at the reason. /g/QRPLabs/message/17690It would be interesting to see if he is actually correct, removing turns to make the LPF more efficient. I'm not sure if anyone did this first. SM capacitors may simply just not heat up so much. Measuring capacitors after they have been stressed may give misleading results. 73 Alan G4ZFQ Glenn VK3YY had a similar problem - solved by replacing LPF capacitors: /g/QRPLabs/message/16511?p=,,,20,0,0,0::Created,,qcx+rising,20,2,0,6073488,?and indeed I have found that there is no lag at the input to the LPF at the C29-LPF junction.
More investigations to follow ..
73,
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Re: My 40M QCX shipped yesterday!
Same here! Excitement mounting.(S.N. 2383)
I've already built one, and it worked beautifully until I messed it up.
Soon I'll be able to use my new one to compare voltage readings, waveforms etc. and get the original one back up and running - I hope!
73, Julian G4ETS
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Re: QCX 80 Transceiver - Connection for a Straight Key
Hans,
Is this still on the agenda? ?Auto detect would be nice but a menu option will do.
Regards
Simon VK3ELH?
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Power lag issue on QCX
#qcx
On key down at low supply voltages there is a lag before reaching the final power. Example: For a 11.5V supply it starts at 1W, and there is a delay of several seconds before a fairly rapid increase, reaching the final value of 2.3W. Glenn VK3YY had a similar problem - solved by replacing LPF capacitors:? /g/QRPLabs/message/16511?p=,,,20,0,0,0::Created,,qcx+rising,20,2,0,6073488,?and indeed I have found that there is no lag at the input to the LPF at the C29-LPF junction. More investigations to follow .. 73, Euan
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Hi all
This is a monthly reminder of?guidelines?for?posting?to the QRP Labs group. Keep these?guidelines?in mind when?posting?to the group.? - Remember your email goes to up to 2500 people - so ask yourself, is it something you really want 2500 people to see?
- Before asking a question, please ensure you have read the relevant manuals and web pages thoroughly, to see if your question is already answered somewhere.
- Also check the FAQs??and??
- Don't write about your kit arriving. Send that to?sales@...?instead - where it is compiled into statistics published here?
- For any questions about shipping or your order, please email?sales@...?instead
- In the event of any missing or damaged component, please email?sales@...?instead
- Please don't write "Happy Christmas", "Happy New Year" etc messages - it's very nice of you but imagine if all 2500 members wrote it...
- It is nice and friendly, to provide your name and callsign - or if you wish, you can add a photograph and whatever details you like, to your profile:?/account?page=profile&profilesubid=0
- Use tags to label the subject; a list of tags is available when posting to from the web interface, or just type in the subject line e.g. #qcx if your post concerns the QCX transceiver kit
- If you are asking for help with a problem, please provide as much information as possible about your problem; "Doctor I feel sick" never helps the doctor to diagnose much, without a lot of further questions; it saves time and messages, if you provide as much information as you can at the outset.?
- If you change the topic of a thread, please edit the subject line or start a new thread, to keep the content and subject lines relevant.
- Remember, a lot of people in the group are hobbyists trying to help other hobbyists for free and in their own spare time.
- If you find the volume of emails too high, remember that you could also configure your group membership to send you "daily digest" emails, collecting all posts for a day into one; or you can configure it to group 12 posts in one email.?
- Be NICE... remember, it is easy to misunderstand each other over email: when we cannot see each others faces, we miss a lot of emotional indications
Thanks & 73 Hans G0UPL
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This checker is ready build , not a kit , for 45 Euro? (-:
73 John
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Here is a FB copy of the AADE :
73 John
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Hi Sean
10K is correct. See?
73 Hans G0UPL
On Thu, Jan 18, 2018 at 12:15 AM, Sean W7SKD <sean.jrdalys@...> wrote: I'm working through a build of the QCX, and noticed that the trimpot in my kit (R47) may be incorrect - it is marked '103' (10K value)? instead of '104' (100K value) as the instructions call for.? Are the instructions correct (is R47 in fact supposed to be a 100K trimpot), or is the component in the bag correct (is R47 supposed to be a 10K trimpot)?
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I'm working through a build of the QCX, and noticed that the trimpot in my kit (R47) may be incorrect - it is marked '103' (10K value)? instead of '104' (100K value) as the instructions call for.? Are the instructions correct (is R47 in fact supposed to be a 100K trimpot), or is the component in the bag correct (is R47 supposed to be a 10K trimpot)?
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Several years ago I built several SMDR kits, I had bought a Commercial type LC meter but it wouldn't read the coils, then I found out about the AADE LC checker kit, easy to build and all of us that were building the kits, and a lot of kits later, found that the readings were almost right where they were suppose to be, we learned a lot about winding coils, one kit only required a few turns and at first we wound the coil with the leads close together, big mistake, watching the meter we spread out the coils until we got the proper readings, there was something different about the reference frequency the AADE kit used, it still works, as long as I remove the battery when I'm not using it and when I do use it, make sure I go through the calibration procedure as specified in the instructions.? I was sorry to learn that the owner became a silent key and the kits are no longer available, they were great for QRP kits, hopefully someone will come up with something close to what AADE made.
John K2IZ
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On Wed, Jan 17, 2018 at 3:48 PM, J68HZ <bill@...> wrote:
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The trouble with all of these LCR meters is rarely do they test at frequencies where you will be using the parts. ?The best solution ive found is to set up a test jig with my spectrum analyzer with a known capacitor or inductor in an LC circuit. ?Then scan/ measure at the frequency of use. ?Ive been a bit hard headed about trying to find the perfect LCR meter myself, but it doesn't exist.?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it:
email:??bill@... ?
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On Jan 17, 2018, at 2:51 PM, Roger G4IUP < rogerlimbert14@...> wrote: Hi all, I use Peak Electronics LCR45.? It is not cheap but it is good. The DCA ?Semiconductor Analyser ?is also good.
73 Roger G4IUP.
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Colin Buckup
Alan de G1FXB
barry NF1O
John PD7MAA
J68HZ