looks real good. love that delay on output relay. that also helps if loose power to one side . safe shut down. having shipping delays in NY as well. lots of extreme weather in the US . nice combiners. I got a lo pass filter board coming from same company. like how you found where to put a cap to take out AC hum on un reg supply. The last repair I did was a wile ago now. I used a optocoupler in the keying circuit . and a HV IGBT to key relay. old tube amp. now has 12V soft key PTT for any radio. 73's
Awesome safety circuits! Knock on wood...my 1 device is going strong! I must be running it correctly and not abusing it. I use a separate relay buffer from Radiodan off eBay and leave the auto key switch off. Love this box! All reports say I sound really good with my IC7300 and Heil Sound Pro 7 headset...going out thru the Double Bazooka vertically hung dipole.
I bet you dont use the auto-key feature but use the RCA jack which is the way to go. I never had a failure of the device when keys using an RCA Jack. All the failures were only while using the auto key feature.
I would also incorporate a 0.1 Ohm high-power resistor between the two positive leads. This guarantees that both LDMOS transistors receive identical voltage, leading to a more balanced operation. Moreover, in the event of a fuse blowing, there will still be ample current to dissipate the stray RF. Additionally, I would attach a thermal switch to the 0.1 Ohm resistor. Utilizing a DPDT NC relay, this switch will cut off the power supply if the balance resistor overheats.
Thats a really good idea, the reason I was hesitant to incorporate any of that is because power supplies go haywire literally when you connect them together even with a 10k resistor. I am talking about under a no-load condition they start clicking and and cycling as they are not capable of load sharing. so I strictly keep the 2 devices isolated.
Congratulations on the dual LDMOS build. I don't think the Bird 43 is designed for accurate power measurement of the complex AM waveform. You're better off measuring peak envelope power in the SSB mode from the transceiver. This will give a more honest result. Just my 2c, your mileage may vary.
Love the safety capacitor on the output relay! For power supplies, wondering if you have tried Huawei R4875G1? This PS has stock volts of 53.5v but can be over-volted to 58.5v with a simple CANBUS / arduino connection. Huawei puts out a solid 75 amps at 53.5v and about 69 amps at 58.5v without breaking a sweat. Single PS is about $235 USD delivered. Only downside is you have to connect up your own 240v power cord because the Huawei's are made for 24 hour use in Cell Phone Towers to charge battery backup power supplies, to keep cell towers operating during main power outages. 240v AC and 50v DC connects to back of PS using PCB style connector, but it's easy to solder on wires, just not as elegant as S-3000-70's which come with a power cord. One more downside of Huawei's are a noisy 18,000 RPM cooling fan, but it's easy to remove the fan and replace with 4000 RPM version that is MUCH quieter but still keeps PS cool. Huawei's are also made to be connected in parallel, just like Meanwell RSP-3000-48, but if you decide to parallel 2x Meanwell's or 2x Huawei's then take care to read the instructions in the datasheets which tell you how to parallel them safely. RSP-3000-48 also has built-in current sharing function just like Huawei, and up to 3 units can be connected in parallel to provide higher output current. Output voltage on Meanwell can also be programmed up to 56v which is not 64v like you show in video, but even 56v will still push these LDMOS FETs to 2500-2700 watts RF, and honestly a 300w difference is not super significant from RF point of view. Retail price on Meanwell's are too high, around $500, but I have seen wholesale China distributor prices for Meanwell's that essentially same cost as the the S-3000-70 that you show in the video. Appreciate all the cool videos, amazing work you are doing! 👍
Thanks for your input, I always enjoy your reading your comments. Finding a 65v power supply that doesnt emit lots of switching noise was a challenge. I actually have a meanwell laying around and it causes about 7 s units of noise on my radio irregardless of how much ferrites I put on it. I think it emits noise through the input. And s-3000-70 doesnt come with any wires at all. Power cord has to be wired separately as well as the output cables.
@@NeedleBender785 Your right about the Meanwell, they radiate RF wicked bad on the 240 AC lines but that is because the datasheet of Meanwell shows it is EMC Class A (i.e. May cause radio interference with other equipment). To make the Meanwell meet EMC Class B (will not radiate RF), you have to add an EMC/EMI In-Line Filter because ferrites alone will only filter out common mode RF, ferrites do not filter differential mode RF noise. When I use Meanwell, I also add 240V AC in-line filter NAC-20-472 (Mouser Part# 436-NAC-20-472) which is a commercial grade AC filter (Class B) and it knocks the RF birdies down from S9 to zero (0), this filter does an amazing job for only $32 dollars and well worth the money! Fortunately, the Huawei R4875G1 (75 amp) and R4850G2 (50 amp) are rated to EMC Class B, and so they do not need a 240 AC differential mode filter at all thankfully, probably because these supplies are made to work in telecom equipment like cell phone towers.🙂
Very nice looking product 😁
💪💪💪
looks real good. love that delay on output relay. that also helps if loose power to one side . safe shut down. having shipping delays in NY as well. lots of extreme weather in the US . nice combiners. I got a lo pass filter board coming from same company. like how you found where to put a cap to take out AC hum on un reg supply. The last repair I did was a wile ago now. I used a optocoupler in the keying circuit . and a HV IGBT to key relay. old tube amp. now has 12V soft key PTT for any radio. 73's
Thats interesting, thanks for sharing.
Very impressive ! Clean as you can get !
Love it and surely make base station get across the street😎
Thanks!!!
Awesome safety circuits!
Knock on wood...my 1 device is going strong! I must be running it correctly and not abusing it. I use a separate relay buffer from Radiodan off eBay and leave the auto key switch off. Love this box! All reports say I sound really good with my IC7300 and Heil Sound Pro 7 headset...going out thru the Double Bazooka vertically hung dipole.
I bet you dont use the auto-key feature but use the RCA jack which is the way to go. I never had a failure of the device when keys using an RCA Jack. All the failures were only while using the auto key feature.
I would also incorporate a 0.1 Ohm high-power resistor between the two positive leads. This guarantees that both LDMOS transistors receive identical voltage, leading to a more balanced operation. Moreover, in the event of a fuse blowing, there will still be ample current to dissipate the stray RF. Additionally, I would attach a thermal switch to the 0.1 Ohm resistor. Utilizing a DPDT NC relay, this switch will cut off the power supply if the balance resistor overheats.
Thats a really good idea, the reason I was hesitant to incorporate any of that is because power supplies go haywire literally when you connect them together even with a 10k resistor. I am talking about under a no-load condition they start clicking and and cycling as they are not capable of load sharing. so I strictly keep the 2 devices isolated.
Congratulations on the dual LDMOS build. I don't think the Bird 43 is designed for accurate power measurement of the complex AM waveform. You're better off measuring peak envelope power in the SSB mode from the transceiver. This will give a more honest result. Just my 2c, your mileage may vary.
Love the safety capacitor on the output relay! For power supplies, wondering if you have tried Huawei R4875G1? This PS has stock volts of 53.5v but can be over-volted to 58.5v with a simple CANBUS / arduino connection. Huawei puts out a solid 75 amps at 53.5v and about 69 amps at 58.5v without breaking a sweat. Single PS is about $235 USD delivered. Only downside is you have to connect up your own 240v power cord because the Huawei's are made for 24 hour use in Cell Phone Towers to charge battery backup power supplies, to keep cell towers operating during main power outages. 240v AC and 50v DC connects to back of PS using PCB style connector, but it's easy to solder on wires, just not as elegant as S-3000-70's which come with a power cord. One more downside of Huawei's are a noisy 18,000 RPM cooling fan, but it's easy to remove the fan and replace with 4000 RPM version that is MUCH quieter but still keeps PS cool. Huawei's are also made to be connected in parallel, just like Meanwell RSP-3000-48, but if you decide to parallel 2x Meanwell's or 2x Huawei's then take care to read the instructions in the datasheets which tell you how to parallel them safely. RSP-3000-48 also has built-in current sharing function just like Huawei, and up to 3 units can be connected in parallel to provide higher output current. Output voltage on Meanwell can also be programmed up to 56v which is not 64v like you show in video, but even 56v will still push these LDMOS FETs to 2500-2700 watts RF, and honestly a 300w difference is not super significant from RF point of view. Retail price on Meanwell's are too high, around $500, but I have seen wholesale China distributor prices for Meanwell's that essentially same cost as the the S-3000-70 that you show in the video. Appreciate all the cool videos, amazing work you are doing! 👍
Thanks for your input, I always enjoy your reading your comments.
Finding a 65v power supply that doesnt emit lots of switching noise was a challenge. I actually have a meanwell laying around and it causes about 7 s units of noise on my radio irregardless of how much ferrites I put on it. I think it emits noise through the input. And s-3000-70 doesnt come with any wires at all. Power cord has to be wired separately as well as the output cables.
@@NeedleBender785 Your right about the Meanwell, they radiate RF wicked bad on the 240 AC lines but that is because the datasheet of Meanwell shows it is EMC Class A (i.e. May cause radio interference with other equipment). To make the Meanwell meet EMC Class B (will not radiate RF), you have to add an EMC/EMI In-Line Filter because ferrites alone will only filter out common mode RF, ferrites do not filter differential mode RF noise.
When I use Meanwell, I also add 240V AC in-line filter NAC-20-472 (Mouser Part# 436-NAC-20-472) which is a commercial grade AC filter (Class B) and it knocks the RF birdies down from S9 to zero (0), this filter does an amazing job for only $32 dollars and well worth the money! Fortunately, the Huawei R4875G1 (75 amp) and R4850G2 (50 amp) are rated to EMC Class B, and so they do not need a 240 AC differential mode filter at all thankfully, probably because these supplies are made to work in telecom equipment like cell phone towers.🙂