Project was to build a 902.313MHz beacon to replace a local one that was off the air.
Beacon Project status: Operational
Beacon AMP Project status: Operational
Installed on Joanna Bald 21 November 2022
*** Frequency 902.31199 ***
7 December 2022 - Dex W4DEX reports... 902.312 beacon can be received here in EM95tg almost every evening and morning. Weak but readable now at 8:30 pm. The few times I've listened for it around midday or afternoons, I could not hear it. I believe there are some ridges blocking the signal to the east. I've never been able to copy the 432 beacon all the time.
23 November 2022 - Doug KG4WLX in Knoxville reports 902 beacon 10 over s9 and Vic WB4SLM reports hearing it at both his Hayesville QTH and at his Centerville QTH.
22 November 2022 - Receiving it just fine in EM85aq (Maryville, TN). Scott N0EDV.
21 November 2022 - 902, 1296 & 2304 Beacons Installed. Audio of 902.31199 beacon from my home system.
The beacon shack is behind this shack - beacon tower in middle of picture.
17 November 2022 - Install date confirmed.
14 November 2022 - Ott had to postpone the install. Tentative new install date is November 21.
8 November 2022 - The plan are to install the beacon on Joanna Bald on November 15 at 2:00pm.
2 November 2022 - Received the 902 M2 17-element antenna for my station and put it up with the 902.313 beacon attached - pointing south - let me know of any reception.
26 October 2022 - The beacon temporarily removed from testing.
23 October 2022 - Beacon placed on my front porch and connected to a 900MHz Comet KP-20 antenna on a gin-pole on the new tower base temporarily - see below plus moved the keyer board inside the beacon case.
17 October 2022 - No reports of the beacon being heard with it at my home location except me up at Brasstown Bald - W4DEX tried, WB4SLM tried and W4ZST tried - noting heard. I will be moving the antenna later this week to the tower my other antennas are on.
10 October 2022 - Drove up to Brasstown Bald parking lot (7.5 miles east) and heard the 902 beacon on my Malachite handheld with a rubber duck in the car. Hear it in video below.
8 October 2022 - Vic (WB4SLM) down near Macon has been listening for the beacon and I moved the antenna up on a mount on my roof - still nothing heard by Vic.
7 October 2022 - Testing with antenna outside and beacon equipment on screened in porch.
6 October 2022 - Q5 amp arrived - testing in lab - getting 35W+ on long keydown.
5 October 2022 - Preparing for the Q5 amp - the beacon board has a BIAS circuit at 6v which is on during keying - I will use the circuit below to send a ground to key the amp.
4 October 2022 - The Q5 amp shipped.
3 October 2022 - Corey at Q5 says the 25W amp with 20mW drive capability should be ready to ship soon.
25 September 2022 -The Mitsubishi AMP module for the K5TRA board finally came in - going to continue with the Q5 Signal AMP for the beacon.
21 September 2022 - I have given up on the AMP module for the K5TRA AMP board - it's been lost at USPS for two weeks and I have asked for a refund.
I have ordered a Q5 Signal 25W PA and Corey is going to build it so it will supply 25W with 20mW input.
http://q5signal.com/index.php?route=product/product&path=68&product_id=79
15 September 2022 - Beacon working fully - I replaced the IRLM2060 and the beacon is working fully.
I am still waiting on the AMP module for the K5TRA AMP board - I contacted the seller yesterday as USPS tracking shows "acceptance pending" - he is checking into it.
14 September 2022 - I have the beacon working again - I replaced the BC807 and it still didn't fix the issue - I removed the IRLML2060 and it started working so I suspect it now - I will replace it later today and see if that resolves the issue. IRLM2060 controls the PA bias circuitry so not needed at the moment. See beacon back in action in the video below.
13 September 2022 - Testing to find the issue - power out is a constant 20mw and the BC807 transistor is constantly closed - I should be able to replace that later today and get this working again.
12 September 2022 - After getting this all packaged for test (except the K5TRA amp) it worked well for a while but the beacon quit working a few days ago - it is still putting out a signal but the keying stopped - the keyer is fine - more tests are needed this week to find the issue and still waiting on the chip for the K5TRA amp board.
7 September 2022 - I put the K1EL keyer in a small case so there are no loose wires - still waiting on the RA20H8994M amplifier to arrive.
3 September 2022 - Ott had to postpone our meeting but I was able to package up the beacon today. I am going to proceed with the K5TRA amplifier to replace the small Chinese amp shown below. I should have a Mitsubishi RA20H8994M amplifier replacement chip next week.
Close to getting the 902 beacon back on-air!
2 September 2022 - I will be meeting with Ott W4WSR at his home Sunday to package up the 902.313 beacon with the others (1296 & 2304) so they can be put back up at the beacon site in Western NC (EM85cg).
Working with the Si530 installed!
30 August 2022 - Video of beacon reception from SDR Console on my Pluto Plus.
29 August 2022 - The Si530 oscillator chips arrived and I have installed one on the first beacon board.
Beacon board only - 19mW below - this was after I added the 68uF capacitors back at Cs.
Good News!
26 August 2022 - The Si530 oscillator chips left Hawaii and arrived in Memphis this morning and are expected to arrive here Monday.
Here's a link to the datasheet for the Si530.
https://www.skyworksinc.com/-/media/Skyworks/SL/documents/public/data-sheets/si530.pdf
25 August 2022 - Just received word that the three sample Si530 and three sample Si549 oscillator chips have shipped via FedEx from Singapore. I am particularly excited to get these - the Si530 is what is specified in the beacon, but the Si549 is programable via an I2C bus.
Success!!!
14 August 2022 - This is what the beacon looks like in the lab.
Success!!!
12 August 2022 - Hooked up the keyer and the beacon is alive! Listen to the beacon with a KID2 keyer. Still no PA but soon!
12 August 2022 - found two bad solder joints between the ADG901 and ADG902 switches and I bypassed the two DC blocking caps since the DigiLO has a blocking cap. Now seeing 3.213dBm/2.10mW. Now to test the AMP.
12 August 2022 - I spoke with Corey at Q5 - he suggested I temporarily bypass all the switches and connect right to the input of the SGA6486 - I did this and got 12.443dBm/17.6mW. Next I will remove the DC blocking capacitors and jump the pads and try with the DigiLO connected to the pads for the Si530.
12 August 2022 - Did a continuity test through the ADG switches and all was fine - it looks like there is too much capacitance on the DC block - this would be an easy fix and good news - I'll be calling Q5 today to see what their thoughts are on this. More on this soon.
10 August 2022 - The SGA6386 was replaced with a SGA6486 - no difference. Next to trace through the ADG switches.
9 August 2022 - I was able to get in the lab today and replace the ADG919 - tested and still seeing a very low output - will replace the SGA6386 with a SGA6486.
9 August 2022 - I received an email from the local Skyworks representative and she said the updated expected ship date of my samples (Si530, Si540 and Si549) is September 9, 2022 - this is much better than the initial 365 day estimate I first received. I will continue to use the DigiLO in the meantime but being able to get one of these will make the project much more compact.
Also, I had to order some more ADG919 switches to replace the one I removed - those will be here today.
1 August 2022 - Was able to get to the lab today to look at voltages on all the switches - I found the ADG919 was not seeing the proper voltage at pin 1 (Vdd) - I have removed it and will re-solder it soon - I believe it was shorting out on an adjacent pin.
Stay tuned on this one - hopefully replacing it solves the issues and I can get this operational and move on to testing the PA.
30 July 2022 - Starting to trace the switches - red dot is pin 1 (Vdd) and blue lines are input and output.
27 July 2022 - Checked power to SGA6386 and it is fine. Below is the schematic for the beacon board.
26 July 2022 - Tested all the traces from switch to switch - found one side of one switch was not soldered down - fixed that and all my solder work on the switches is good. Next test is to check voltage to the SGA6386 preamp.
I may remove and replace this ADG901 below - I don't like the alignment, but going to do some other testing first - example see the output before the SGA6386 and other points in the switches - I have another set of SMA pigtails coming for that test.
25 July 2022 - Back in the lab to resume testing after a week of vacation.
After passing through the beacon board I get -23dBm which is not good. Next step is to check the ADG9xxx switches and the SGA6386 preamp.
The setup in the lab below.
14 July 2022 - Here is the exciter board with the DigiLo driving it. This is SDRConsole using a Pluto Plus transceiver.
13 July 2022 - Getting ready to test the PA with the beacon board. Need to replace the blue wire (PA Bias) on the PA with a green wire. Waiting on the 1.2nH 0805 inductor for the PA board - I ordered some from Mouser and they will be here Friday - the ones I ordered from eBay will probably arrive next week.
10 July 2022 - I was able to adjust the pot on the beacon board and get 5.6v out of it - this should be plenty to bias the PA. Below is a direct screen capture from the SA. Purple is keyed and yellow is un-keyed.
09 July 2022 - Beacon Testing Success - I installed the remaining parts and hooked the DigiLO to the beacon board - success!
The only issue I saw was there was not 6v present on the PA Bias line when the beacon was keyed - I will investigate this one further.
Below Yellow is keyed and purple is un-keyed - a couple of dBm difference - this is not a scientific test as the SA had an antenna as did the beacon board.
08 July 2022 - Installed the 7.9nH inductors (Ls) - all that's left is to install the 1.1nH inductor (Lt) which is at the line between the pad near Cb and the large ground pad (middle of board on right), and then the RF in and RF out, power and connect the bias.
07 July 2022 - Installed a fused 12v lead and ground and tested voltages on the regulators - all voltages tested good and the fuse was fine. I ordered some SMA pigtails for this and the PA board and they should be here Saturday. The ADG918 switches are in the US and will be here soon. I also installed a wire to test the PTT function to key the board.
06 July 2022 - Installed the BC807 transistor. I am still waiting on the ADG918 switches - I have the ADG901 switch, but waiting to install the ADG918 switches first.
03 July 2022 - I installed more parts - for the beacon board I am still waiting on the ADG918 switches and the BC807 transistors - I have the ADG901 switch.
I hope to have the remaining parts and test this in the next two weeks.
Last week I received an email from a company in Atlanta which represents Skyworks - I spoke with them and they are ordering samples of the Si530 P/N: 530AC902M313DG (902.313MHz) oscillator for me - if these take too long I have a DigiLO from Q5/DownEast Microwave set for 902.3125. I also asked about samples of the Si540 which is pin compatible with the Si530. Finally I also asked about samples of the Si549 which will come programmed with the requested frequency but is also programmable via I2C. Hopefully I can get samples of one of these quickly.
Beacon Board below
25 June 2022 - more parts arrived and I installed them.
14 June 2022 - more components arrived today and I installed them.
13 June 2022 - adding components as they arrive.
8 June 2022 - Added the 10uF capacitors.
7 June 2022 - The PA boards arrived (one on right) and some more of the parts have arrived.
4 June 2022 - Found a few more parts I had on hand and received the 5k pot and installed it. I am about to order the remaining capacitors and resistors.
3 June 2022 - Added a few SMD parts I had in my possession from an SMD assortment I purchased on Amazon months ago. I will need to place an order for the remaining capacitors and resistors. I have ordered all the large parts - voltage regulators and switches (ADG901, 902, 918, and 919). Waiting to hear back from Digi-Key on the Si530 oscillator.
2 June 2022 - Beacon boards arrived - see below. Adde 1/4W 13ohm resistor.
27 May 2022 - Started a project this week to build a 902.313MHz beacon to replace a local one that is off the air.
Found the following from Tom K5TRA - http://k5tra.net/TechFiles/A%20Common%20Design%20for%206M%20Through%2033CM%20Beacons.pdf that looks interesting and I have ordered the bare boards from JLCPCB.
