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Re: Get to know your dental hygienist!

 

Careful with that scaler Eugene (Pink Floyd).



--
- 73 de Andy -
Re: Get to know your dental hygienist!

 

¿ªÔÆÌåÓý

I second that. Got some myself from my dentist. VERY useful.

73,
Cliff, AE5ZA



On Jan 15, 2024, at 14:07, Rick Williams - VE7TK via <ve7tk@...> wrote:

I recently completed my QMX 20 - 10m radio. The construction went very well. It went so well in part because of my wonderful dental hygienist!

On a visit last fall for my annual cleaning I spoke to my hygienist about building some new electronics. I was complaining about the detailed work involved especially ensuring that there were no shorts between component parts. She nodded politely and the cleaning continued.

As we were finishing up she disappeared and returned with some dental tools in a sterilized package. She handed them to me and informed me that these were past their useful lifetime and perhaps they might be of use to me!

EUREKA!! These tools are absolutely perfect for scraping at the area between traces on the QMX. With some magnification you can quickly evaluate if that "glob" is a solder bridge or just some flux! I also found them useful for compressing or spreading out coils on the LPF toroids. Definitely a useful addition in the shack!

Get to know your hygienist ...
--
73, Rick
VE7TK

Website: <PXL_20240115_194138953.jpg>
Get to know your dental hygienist!

 

I recently completed my QMX 20 - 10m radio. The construction went very well. It went so well in part because of my wonderful dental hygienist!

On a visit last fall for my annual cleaning I spoke to my hygienist about building some new electronics. I was complaining about the detailed work involved especially ensuring that there were no shorts between component parts. She nodded politely and the cleaning continued.

As we were finishing up she disappeared and returned with some dental tools in a sterilized package. She handed them to me and informed me that these were past their useful lifetime and perhaps they might be of use to me!

EUREKA!! These tools are absolutely perfect for scraping at the area between traces on the QMX. With some magnification you can quickly evaluate if that "glob" is a solder bridge or just some flux! I also found them useful for compressing or spreading out coils on the LPF toroids. Definitely a useful addition in the shack!

Get to know your hygienist ...
--
73, Rick
VE7TK

Website:

Re: QSX: I'd like to purchase a fully assembled & tested QSX

 

On Mon, Jan 15, 2024 at 02:29 PM, Bill wrote:
You mean QS SEX???
Uh oh, I've got visions of users at Hamfests dressed as QRP Labs products now.

There's a similar related medical condition for that -



Don't forget to remove your callsign badges folks ;-))))
?
--
- 73 de Andy -
Re: QMX: Filter issues

 

Stefan,

The next thing to test is the pins 10, 11, 12, and 13 of IC402.? The selected filter should be 2.5 volts, and the others should be close to zero.

If the above checks, test that Q508 is turned on while receiving.? The source and drain should be close to zero volts.

The last check would be testing the low-pass filter diodes and toroid connections.? Only the two for the selected band filter should be one of the six diodes, measuring close to zero volts on the banded (cathode) side of the diodes.? The other diodes should be close to the input voltage to the QMX.? Both toroids in the LPF connection are required to get the diode to switch on.

I am discounting the quadrature sector and T401 based on the discrimination of the sideband, though at a low level.? That would not happen if there were an issue with the I/Q processing through the audio codec.

Others in the group may have different ideas and may be better at isolating the problem.
73
Evan
AC9TU
Re: QSX: I'd like to purchase a fully assembled & tested QSX

 

That last image shows my QSL card next to my Knight-Kit T-60 which was built on April 6, 7 1963 by American WW2 hero Jacob Beser, W3NOD and his son, Eric Beser, KN3UHF. You can read all about Lt Beser at:
Re: QSX: I'd like to purchase a fully assembled & tested QSX

 

Here is the power supply I ordered.
Should be safe for most things!
Re: Seeing my own messages?

 

Thank you John & John.

Glad to see my efforts were not in vain.

I have over a dozen groups.io accounts, and seem to get my messages repeated back to me only on some of them. For QRPLabs, I receive the full digest only (due to the large amount of traffic here).

Thunderbird is used for e-mail and a search does not reveal anything useful about "On Behalf of" in their on-line help. The messages I sent are not in my local e-mail Junk. The digests that I receive contains others' messages, but skip the one I sent. This makes me believe that this is likely a QRPLabs policy? Guessing...

BTW, the search link John presented shows all messages with all mentions of my callsign, not just the messages I authored. I guess that is good... hi.


--
73 de Bob, K6XX


--
73 de Bob, K6XX
Re: QMX: Filter issues

 

¿ªÔÆÌåÓý

Hi Evan,

thank you so much for your reply.

Am 15.01.24 um 00:56 schrieb Evan Hand:
If a Rev2, the symptoms are typical of an IC402 failure.? This can be verified by measuring the bias voltage on pin 9 of IC402.? It should be close to 2.5 volts.

It's a REV 2 (without the suggest diode mod yet) and I measure 2.47 Volts powered up in "receive" mode on Pin 9 of IC402.

If that's saying IC402 ist good. - Very well ... I hate soldering SMD ICs.

However, where to look then?

Thanks again an Vy73

Stefan.



_._,_._,_
-- 
Stefan U. Hegner    <db4st@...>
              * * *
DB4ST --- German Ham Radio Station
D-32584 L?hne ----- Locator JO42IE 
              * * *
GPG-Key | C3CC 23A4 FBA8 622B 48AE
F-Print | 4F19 D0EE E39E ABDC 2BCE
Re: clock contrast mod #clock

 

On 15/01/2024 17:01, Bryan Curl wrote:
Anyone?
Bryan,

The manual says

a) A 220K resistor at R4 (this resistor is not
supplied in the kit, OR
b) A jumper wire in the position shown, and
NO R4.

The picture shows 4 holes.
Looks like the jumper takes 2 middle holes, the resistor spans where the jumper was.

I reckon if you put the jumper in the 2 top holes then the control would not work.
Degree of contrast random.

73 Alan G4ZFQ
Re: Seeing my own messages?

 

¿ªÔÆÌåÓý

Here's what a search of topics shows you've sent.


Could be your email client. Some won't display messages from yourself in a thread. The "On Behalf of" ?confuses them.

Some list software really messes with the internet headers.


From: [email protected] <[email protected]> on behalf of Bob Wolbert, K6XX <k6xx@...>
Sent: Monday, January 15, 2024 10:17 AM
To: [email protected] <[email protected]>
Subject: [EXTERNAL][QRPLabs] Seeing my own messages?
?
This email originated from outside of Samford University. Please consider carefully whether you should click on any links, open any attachments, or provide any information.


I replied to a couple of messages here, but did not see my post. Is there? a place to enable self-posts by logging into groups.io, or is this? set up as an individual group option?

Given recent e-mail difficulties on my side, it would be reassuring to confirm messages written were actually delivered...

73 de Bob, K6XX






--
John KY4WW
Re: clock contrast mod #clock

 

I may have answered my own question.
I'm wondering if the 220k resistor needs to bridge over two holes instead of one. I have one lead of the R4 the resistor in the top hole where the jumper was and then slipping over one moving down,? if that makes sense. there is only one blank hole under the resistor.?
Anyone?

--
regards,
Bryan, N0LUF
Re: Seeing my own messages?

 

GM Bob,

I have to check my Spam/Junk files to retrieve many emails from legitimate.IO accounts¡­¡­ even after reporting them as not spam??

John
KK4ITX

?Each mistake is a learning opportunity.?

On Jan 15, 2024, at 11:17 AM, Bob Wolbert, K6XX <k6xx@...> wrote:

?I replied to a couple of messages here, but did not see my post. Is there a place to enable self-posts by logging into groups.io, or is this set up as an individual group option?

Given recent e-mail difficulties on my side, it would be reassuring to confirm messages written were actually delivered...

73 de Bob, K6XX
Seeing my own messages?

 

I replied to a couple of messages here, but did not see my post. Is there a place to enable self-posts by logging into groups.io, or is this set up as an individual group option?

Given recent e-mail difficulties on my side, it would be reassuring to confirm messages written were actually delivered...

73 de Bob, K6XX
Re: current-limited power supply.

 

There is a Adjustable voltage/current limit board on AliExpress for about $10
( 0-30v 0-3A ) search for Nuitool Store or..

0-30v 2mA-3A Cntinuously Adjustable Current Limiting Protection DC Regulated
Power Supply DiY Kit

On 14 Jan 2024 at 17:46, John KY4WW via groups.io wrote:

Ready to start my QMX high band kit build.

The assembly manual recommends using a current-limited power supply for the
first power-up.

What are members using for this. Lowest cost if possible.

Thanks

John KY4WW
Re: QMX TN0110 Heat Sink

 

Been away for a few days but having a look at the new heatsink, adding machine screws is easily accomplished.?

1) A hole can be drilled into the heat sink's center to compress it with a thin layer of compound against the quad set of TN0110 MOSFEts.? At the moment compression is accomplished with the LCD display's plastic quarter-turn tab.? Functional but not as good as a screw passing through.??

2) The heat sink can be moved flush with the back enclosure edge.? A new #4 hole (or two) can be drilled into the bottom enclosure and *tapped* into the heatsink.? ?

3) Finally, a row of multiple holes can be placed along the front and back side bottom enclosure for ventilation.? With enough holes, it may not even require forced air flow, especially with the heat sink bolted against the enclosure.?

The current quad arrangement has the MOSFET source leads at ground potential. I've not considered the viability of reconfiguring the circuit to ground the drain instead.? A simple device rotation isn't possible for several reasons, a diode across the D-S leads being once.? Changing to a P-channel device may offer some possibilities to divert heat from the physically larger drain lead to a grounded heat sink.??

Paul, W9AC
Re: current-limited power supply.

 

I echo everthing Howard says in his mail.?
Although I run some bucks here for various bits of kit, for all building and testing I use a linear in exactly the way Howard describes.
Cerianly not all, but I have encountered some (cheap) buck converters that spike before they settle.?

73s Ted
2E0THH?
Re: QSX: I'd like to purchase a fully assembled & tested QSX

 

You mean QS SEX???
Re: QCX WARC Party - January 2024

 

My 1300Z session:
First on 30m (using my QCX Classic 20m) I worked the "regulars" PA0CMU, DK3UW and OK2BQN, then ... nothing.
With some trouble I could get through the pile up of a SOTA station OK/DL5AZZ/P.
Then went to 17m with my QCX Mini "15m". I got spotted all over Europe, and got two spots in US with 9 and 13 dB, but no replies.
73,
Luc ON7DQ?
Re: QSX: I'd like to purchase a fully assembled & tested QSX

 

I'm retired! Plenty of time!
72 / 73,
Bill, N4QA/4
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