Meshtastic Channel names, PSK, and order in the channel list determine which nodes and channels can interoperate in the mesh.

•June 18, 2026 • Leave a Comment

6/16/26

Channel basics

  • Channel names and order are critical to interconnectivity. For everyone to communicate in a Meshtastic mesh, they must share at LEAST the same primary channel (index 0). In Hawaii and most of the world this channel will be LongFast (PSK AQ==)
  • For a group of nodes to interoperate reliably, the channel lists must be identical and names must be identical.
  • The index 0 primary channel name determines the RF frequency slot the device communicates on. Example:
    • 906.875 mhz
    • Slot 20
  • Active channels must be consecutive for devices to intercommunicate For a secondary channel to interoperate, nodes must share the same name, PSK, and identical index position so the system handles the packet routing correctly.

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FT-857d microphones: MD-100 and MH-31(electret) and working FT-857d Settings. Sep24

•September 8, 2024 • Leave a Comment
MH-31 stock mic but with the dynamic element replaced with a condenser/electret cartridge. On the right, the Yaesu MD-100 dynamic microphone. For me, the MD-100 works better with tone controls engaged.

1. Yaesu MD-100 preferred microphone Settings
Main – select Filter, not ThruFilter,
Tone Control High Emphasis On,
Tone Control Low Cut 1

2. FT-857 Settings
PROC (MFc)- ON (Proc off is not bad sounds warmer)
PROC 25
Mic Gain 25

3. Hand Held Mic with Electret Conversion – modified microphone.
PROC- OFF (MFc)

FT-857 Settings
PROC 25
Mic Gain 25

These settings are for the two microphones I have on hand for the FT857d. These settings determined by listening to the radio on the Waimea Kiwi HF SDR. PROC is brighter, may be punchier, while Proc off may be more natural.

With the same audio settings on the radio, the MD100 is louder with a brighter sound, the condenser mic element placed in the MH-31 mic is warmer but does have some brightness. Both sound fine without artifacts. I do prefer the MD100 but at PROC 25, the two mics sound similar, maybe hard to tell apart when the MD100 tone controls are engage and set as in Section 1 above.

Below: Audacity Spectrum Analysis of received audio from SDR. It seems that I like the sound of a flatter spectrum (see fig 5 and 9 below), and prefer there to be highs present. No compression produces a warmer sound occuring with when there is a boost in gain at 400hz.

FIG 4- MD100 PROC On 50
FIG 5 MD100 PROC On 25 – check out the flat freq response
FIG 6 MD100 Proc Off
FIG 7 Hand Mic Proc Off warm sound compared to Proc On — most natural.
FIG 8 Hand Mic Proc On (50) – odd 12dB drop above 2000hz . 50 may be too high and produces that artifact- brighter but harsher.
FIG 9 Hand Mic Proc ON (25). much better than Proc 50. brighter than Proc OFF. Better here. possibly more punch in noise.

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XLR to 3.5mm Cable for radio shack microphones

•August 18, 2024 • Leave a Comment

I have two microphones, Electrovoice RE50B and Sennheiser ME30 that have XLR cable connectors. The problem was to make/find cables to interface with my TS590SG radio and a Win11 computer. I have built an interface for the TS590SG with a 3mm stereo jack and PTT switch. The computer presents a mono 3mm jack on its audio interface.

XLR Mic cable, 3 pin XLR pins on microphone, 3.5mm TRS plug, male and female XLR plugs
standard XLR pinout: 1 – ground, 2 – positive/hot, 3 – negative
TRS 3.5 mm plug. The 3 connections from left to right: sleeve, ring, tip,

Electrovoice RE50 schematic from their engineering sheet.

Two XLR to TRS cables on Ebay came wired as balanced XLR to 3.5mm F to M (above). This solution works on the ME66 but on the EV RE50 it only worked if the 3.5mm plug was not inserted all the way – disconnecting ring on the plug – but not sure what exactly is going on. The wiring/schematic of the ME66 K6 module which powers the ME66 element, and provides the XLR interface is an unknown. In any case, to accommodate the EV RE50, the 3.5mm plugs required modification, leaving ring open on the TRS plug and connecting pin 3 or R from the XLR to the sleeve/ground of the TRS plug.
Above – pinout that works in my shop for EV RE50 (dynamic) and Sennheiser ME66 (condensor) microphones. Pin 1, ground/shield and Pin 3 – black or white wire in the mic cable go sleeve. Pin 2 Red goes to tip. ring is left open. I should add that this is the wiring of the working professional cable that was originally used with the microphones.

Below: Unbalanced XLR to 3.5 mm (untested).

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Microphones. Sennheiser ME66 , EV RE50, Yaesu MD-100, Kenwood MC43-S

•July 8, 2024 • Leave a Comment
Fig 1. From top to bottom, Sennheiser ME66 shotgun mic, Electrovoice RE50, and Yaesu MD-100

Link: article on microphone specification and what they mean.
https://www.translatorscafe.com/unit-converter/en-US/microphone-sensitivity/6-4/millivolt%20per%20pascal-decibel%20relative%20to%201%20volt%20per%201%20microbar/

Fig 3. Kenwood MC43-S stock microphone.

Fig 4. MC43-S
Fig 5. MC-43S style mic mods. 3.5mm and RCA jack added for external microphone and PTT/Send switch. Internal mic cartridge is disconnected but PTT and up/down work.

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TS-590SG : Keying the IC-2KL Amplifier

•May 30, 2022 • 1 Comment

Introduction. These are my notes for my TS-590SG and IC-2KL linear amplifier. The diagrams are from the IC-2KL manuals. An external linear amplifier keying control requires using the 7 Pin Din REMOTE connector.

The setup I have used for a long time is from the TS590SG User Manual (Fig 1, Fig 2, and Fig 3). The TS590SG In Depth Manual contains more and somewhat different information and reveals an amplifier keying circuit that uses a MOSFET switch (Fig 5) .

I tested (5/31/22) using solid state keying supported on pin 7 of the TS-590SG to reduce relay chatter in the TS-590sg.

Figure 1. User Manual Pg 75 – Connecting a typical amplifier

Figure 2. REAR PANEL (User Manual)

Figure 3. TS590SG USER MANUAL Pg 13 … the REMOTE connector diagram above is as seen from the REAR PANEL like in the diagram above.
Figure 4: In Depth Manual pg 75

Figure 5. In Depth Manual contains information not in the TS590SG User Manual regarding pin 7 RL

Below: from the TS590SG In Depth Manual — on my rig the menus are 59 and 60

Figure 6. TS590G MENU #59

REMARKS

29may2022 – The amplifier keying in the User Manual employs pin 2 (COM) and 4 (MKE) to key the IC-2KL amplifier. There is an audible relay click in the TS590SG when transmitting. In full break in (FBK) mode, the relay clicks on each dit/dah – noisy and obviously puts cycles on that relay — so I don’t engage QSK An alternate and quieter method is to use pin 7 (RL) and GND – using information from the In Depth Manual.

Initially I thought, RL is a bad term for a NON-Relay pin. Speculating that the engineer designed pin 7 to drive a remote relay. When the internal relay is used on Pin 4, RL pin 7 provides 12v to GND ( the shield on the DIN connector) which may drive a remote 12v relay?

pin 2 is not ground – it provides the logic reference to pin 4 and is a floating common with no continuity to chassis GND.

GND refers to chassis ground … solder to the shield of the DIN connector to obtain a GND connection.

RESULTS USING RL Pin 7 and Solid State Keying

Worked fine for SSB. I did not do much testing on CW. No relay click on the TS590sg and the IC-2KL keys normally.

Note of caution and something to know more about: Using Pin 7 connected on the TS590sg DIN plug to the RCA jack on the linear, be careful to select options 4 or 5 and NOT settings 2 or 3 which turn 12V on. I do not know what the effect this would have on the linear – I would be interested in further information about that.

ALC – I do not use ALC (rev 2nov23)

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Waimea Base, Oct 2020 to Jan 2021

•January 22, 2021 • Leave a Comment

We vacationed in our house in Waimea on Hawaii island from October to January, riding out the COVID epidemic and scouting out a move from Oahu back to my home island of Hawai’i. I shipped the basics to build a station there : FT-857D, LDG autotuner, an MFJ-4125P power supply with the fan mod, a bunch of hamsticks, and an end-fed EARC antenna matchbox.

Hamsticks. I started with the hamsticks and was able to join the local 40-Meter net on 7088 with reasonable reports in good propagation. The hamsticks do provide basic comms, can be set up in an hour, and don’t require a tuner. I did not test them all ( I have 40m, 20m, 10m and 6m ), but even the 10m hamstick is effective.

End-Fed EARC Antenna : 30′ Jackite pole,supported the wire antenna. I ended up with 102′ end-fed wire up 12 (matchbox) to 30 (pole) to 30 ft (tree). To tune from 6-80m, this antenna needed a counterpoise of 30′ 12′ up and running in the opposite direction well off the ground at roof level. For NVIS inter-island, this proved to be an effective antenna at 100W at 40m, 60m, 80m and 160m, with modest DX performance as well. Reports are that signals were good and equivalent to running power from my Aiea QTH on Oahu. I got many S9 reports, and the usual assortment of Q3/4 and < S8 signals from certain stations that seldom give reports of S9 regardless of my location, To make the difference here will probably require much more gain or much fewer losses, i.e. the next level up in antennas. It seemed to be somewhat lacking on the higher bands. These bands 20m and up, work poorly for interisland. For higher bands, perhaps a shorter aerial would work better. One wonders if the 9:1 can push two radiators. COAX: 50′ RG6

Posted in FT-857D, ft8, Waimea Base
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MFJ-269 Flashing ‘Voltage LOW.0V’ on Power Up. successful repair

•September 6, 2020 • Leave a Comment

***MFJ-269 Rev 4C.*** analyzer on power up shows low voltage 0 flashing. I tried it both on external power and new batteries and have the same problem upon power up. After pressing mode button and check an SWR of an antenna the analog needle works fine and also the frequency readout works right but the digital display for SWR stays at 1.0.

image.png

I went through the schematic, measured voltages, etc, which all checked out OK.  Then I did what I should have done in the first place and called MFJ technical support where Jimmy on hearing the symptoms said, “sounds like a bad crystal. I would start there.”   MFJ had them in stock and mailed one to me for $6.  Got it yesterday – it took a week and made it through the current USPS defunding crisis and Covid pandemic.

Bottom Line.  It was the crystal.  I removed the original, and soldered in the new one and the analyzer is working.

Removing the crystal … I used a soldering iron and tweezers.  This is the wrong way to do this.  The old crystal did pop out under heat and duress, taking the solder pad with it on one side.  The other end kind of popped out –  now I think it might have been a cold solder joint on the other lead.   The right way to remove it would be to use a rework station, slowly heat only the crystal with air until it just lifts off, leaving the pad intact beneath it. 

right.  I actually have a rework station but didn’t want to experiment on this repair.  After all was done I got it out, and found a scrap board … this is the way to do it.  A reflow operation would be iffy without the rework station.

Having gone throug all this, if I were to encounter another of these problems – I would reflow the pads with a rework station.  The left pad might have been a cold solder joint that finally went rogue after five + years of use. Who knows? the crystal might have been good and the problem was solder joint failure. It would be worth a try before getting a new crystal because after all, how does a crystal fail?  Real question. If you know send me a comment!

Back to the real world. 

One crystal solder pad was still good.  The other pad was gone along with the microscopic connecting  lead to the board trace.

I tinned both leads of the new crystal and soldered about one inch of wirewrap  wire ( ~ awg 32 +- ) to one of the crystal leads for the side without a solder pad.  Examine the board with a magnifying glass – you  will see where the pad trace connects to the processor and there is a solder point available.

I also soldered a short piece of  bare wirewrap wire to the other crystal lead to provide a soldering contact point.  I soldered that  to the pad first.  The solder bridge should be enough to hold the crystal in place.

The other end I soldered the jumper wire  to the available contact point – very fortunate there was one. 

Soldering tips : use the finest sharpest point on the soldering iron/pen/station.  Use flux.  Mechanically hold down wires and parts in place or you’ll never get done.

 

Major digression – you can skip this paragraph which has nothing to do with the 269 repair. Soldering Iron – decided to switch to the finest point I had on my Hakko soldering station.   Of course the existing point was jammed in the point holder tube.  I extracted the jammed point with a combination of care and brute force – destroyed the point but preserved the holder tube.  I have a spare fortunately.  Inserted the superfine tip point and the iron was good to go.  Aside – if I don’t periodically disassemble the iron, a tip does eventually freeze/corrode/weld in place – I got it just before real damage was done to the heating element assembly.

 

Posted in MFJ 269, soldering

433 mhz rf module experiments

•June 10, 2020 • Leave a Comment

I had these 433 mhz rf modules in my parts inventory for a copule of years and finally have gotten around to hooking them up to arduinos to experiment with them. 433 mhz is in the 70cm ham band making it legal for ham radio license holders to operate these devices.

transmitter: tx       receiver: receiver

The transmitter puts out it’s maximum signal at 433.85 mhz.  The power level is a question and I’ve seen figures from 1 mw to 15 mw.  To measure would require a voltage reading on a dummy load.

 

Theory of op: Receiver: The receiver antenna feeds a tank circuit which tunes the received signal.  This signal is mixed with the output of an oscillator, apparently  down to baseband.   This baseband signal goes to an opamp circuit to generate the digital signal.  What is it? – a variant of a superhet but without an IF, the output goes to baseband.  This resembles the front end of an SDR without the quadrature detector.

The receiver s/n can be subject to noise – a training preamble in the packet data train greatly increases the range of the system.

Even at this low power the signal can be heard on my mobile radio (FT7900) from a point 400m away.  In an open field I expect further than that.  The modules are designed for Amplitude Shift keying (ASK).

By using this kind of modulation,  digital signals transmitted at 9600 baud are possible over short distances.  In my testing short ranges of 10m are quite reliable.  In the open field, 100 meters and more are possible.

The first experiments directly applied digital serial pulses of 0’s and 1’s to transmit byte streams over an RF link layer.  Raw signalling produced ranges of no more than about 10m.  Use of the ‘RadioHead’ library which employed a packet frame structure and the transmission of a ‘training preamble’ preceeding the digital data transmission, and a CRC field greatly improved the link level signaling.  Depending on baud rate,  range over 100m may be practical with clear line of site.

Trees, the body, rain, walls all reduce 433 mhz signal strength greatly.  Clear line of site is optimal for signal strength.

1/4 wave antennas produce good short distance performance.  High gain antennas have yet to e tried.

Programming technique is also challenging.   I have just succeeded in using memset() to copy the received data frame buffer from it’s raw form as a uint8_t  byte array, to a C struct of floating point numbers, long and short integer data types, and even raw ascii.

 

They are primitive devices, extremely low power,  to see if I there are possible applications, including entertainment or education.  , e.g. for the weather station and a remote sensor… something like that where running data cables is a huge problem.  The Radiohead library http://www.airspayce.com/mikem/arduino/RadioHead/  for the arduino that can be leveraged for data, and a good deal of basic code is available online so it’s easy to get started.

At this point, I’ve breadboarded a test project, and assembled a receiving breadboard with an 8×2 LCD screen to function as a receiver data display.

Range. Range between the transmitter and receiver with simple whip antennas is disappointing,  less than 10m in the vicinity of the house.  ( Others report ranges of 15 to 30m).

But the guy in the open field near Berlin got 300+ m.  Now I think he probably used the RadioHead library to get that range.  Without the library on raw IO on the TX/RX  pins, 10m is about the limit.

Testing on 6/5/2020 with the RadioHead library, and using my car to receive the pulses
I could hear the signals on Iho Pl near the turnaround – 415m or .26miles.  Did not bring the arduino receiver… that next time.  As far as an audible signal, I’m sure it can go farther.

The ham radio tranceiver can tune 433.85 as it is in the middle of the 70cm ham band. The Yaesu FT-7900 has a good receiver.

The RX led on the arduino pulses with the signal from the receiver.  Data detection however requires that the arduino digital pins detect the  This limitation is likely due to limits of the receiver design.  The receiver seems is a simple superheterodyne  design with a tank circuit tuner that renders it susceptible to noise and other interference.  This greatly reduces it’s ability to detect a useable signal using amplitude shift keying (ASK).   The UHF ham radio receiver is vastly superior and with it I have been able to hear the transmitter long after the digital receiver stops picking up data packets from it – even though the RX led still pulses weakly along with the transmitted signal.

The Radiohead library employs technique of sending a training sequence 36 bits called a “training preamble” that allows the receiver AGC to settle down, before hitting it with the data package of bits.  The RH library employs a packet format, with a 16 bit CRC to enable the receiver to determine if the packet was received intact.  I

There is surely a way to process the AFK signal from the FT-857, say with a raspberry pi.  The USB signal

Sources:

https://lastminuteengineers.com/433mhz-rf-wireless-arduino-tutorial/
This is a good starting place using the RadioHead library.

markfickett kb3icy, github arduino-morse from kb3jcy

https://github.com/markfickett/arduinomorse

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May 2020 – Month 3 of the Pandemic – Radio Activity

•May 24, 2020 • Leave a Comment

It’s May in the year of the COVID 19 Pandemic.  It’s been a while since my last post here and I’m significantly behind, despite being holed up and sheltering in place. A strange time of Zoom virtual meetings online like our EARC club meetings, increased ham net activity – no brainer that one.

Radioactivity

Continue to build matchbox antennas but the field day rush is off – field day 2020 is going to be a ‘field day alone’ or ‘field day at home’ event.

I revisited my 2M moxon today (5/24/2020) and checked it out using Winlink Express and VARA-FM. At 145.07 mhz measured the front back receive signal difference of 1-2 S units (6-12 dB) and SN ratios of between 5 and 9 dB – at least it is not omnidirectional.

Most significantly I’ve upgraded my digital software suite for WSJT-X. I get much better situational awareness than before. In addition, it’s much easier now to set goals and go after WAS, for example. The work factor is much less and helps interest overcome apathy. We’ll see.

| -- Ham Radio Software - 
|       |-- WSJT-X  2.2.0 -rc1  May 2020
|       |-- JT-Alert 2.16.5
|       |-- DxLab Launcher
|       |-- DxLab Keeper 156.4.9
|       |-- DxLab View Map 4.6.4
|       |-- pskreporter
|       |-- QRZ.com

JT-Alert allows a qso callsign  lookup on QRZ - nice to have, and provides a significant "w/b" worked before

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20 meter opening to Europe on FT8

•May 10, 2019 • Leave a Comment

For the first time I caught a 20m opening with FT8 the last couple of nights and worked stations in the UK, Finland, and France.  9may2109z ~0600-0700

8 may,  the sunspot number was 25.   The sunspots went from 11 on may 4 to 25 by the 8 may( today on 10may N = 25).  I wonder.   Probably unrelated, earlier in the day 8 may the 0900W 40m net was a bust on 40m 80m and 60m – very poor conditions.

euro8may19ft8.png

Working conditions: 20m ft8/wsjt-x, 84′ doublet, linear amplifier – 30/400 W (-13 db), 4:1 #61 balun temp : 43°C

Other:  heard only 25% or fewer stations than could hear me.  reception is 75% of the  problem!  Power probably needed and I used it to make contacts: 400w -13db: calc- 200 -16 db, 100w -19 db.

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