Thanks, Stu, for testing the booster. Last December, I bought the 25 amp version from the same seller for my go box but haven't used it yet. I also bought a low battery switch which would be connected before this device to keep it from taking the battery down too much. As you described, the MFJ has that and other features in the same box which can be opened for troubleshooting, but it isn't as "waterproof" as the XWST Boost Converter. I will purchase the capacitor as you described and keep it in the go box so that I reduce the ripple. 73, Robert
Stuart, your test, the capacitor fix, and your comments seem particularly useful for a non-HAM problem. A lot of folks and I own a Suzuki outboard motor. For about 10 years, these motors had a habit of being tough to start due to a voltage stability issue on a wire powering the Engine Control Module (ECM). Anything at all would cause it, from poor connections, to voltage drops during cranking, to older batteries that weren't completely topped off. It was maddening, and for most owners it still is. That includes me. Then, the thought came that we might use a DC-DC boost controller, waterproof of course, and unfortunately the ones tested reportedly created quite a bit of RFI, and now the wavering voltage you described. Well, with marine VHF our only lifeline (156-162 Mhz), RFI is a red flag, and I wouldn't want to test the effects of the "ripple" on an already voltage-finicky ECM. I'm going to try the XWST and capacitor solution, and because boats all have a battery switch we should be able to connect it and forget it. Thanks much. I'll try and report back on the results.
@@AG6AG drive.google.com/file/d/1wLdBFEmCt4UGaF6MBOsB1sRpd4KlIQYx/view?usp=share_link Stuart, I installed the booster, along with the capacitor on the output, and the engine control module on my Suzuki outboard now seems insensitive to battery voltage. This is a big win. I'm getting a consistent 13.75 volts on the output of the booster. Now, I go back over the endless discussions on "The Hull Truth" and other blogs and see how everyone was just trying to salvage the last remaining hundredth of a volt in order to avoid engine shutdown. There simply was no space left on the board in my boat's bilge access for a new box, so I just mounted the booster and a stainless terminal block. I'm not happy about the capacitor connections, which are just pinned under each screw on the output side. Lots of rough motion could eventually break the capacitor wires, so I need a way to connect leads to the capacitor, and that will permit me to immobilize the capacitor to prevent fatigue. Any advice would be appreciated. Thanks again. - Bill -
Thanks for the look at the low cost option. Be careful leaving it attached to the battery for a long time - even the MFJ must be turned off or it will run the battery down after a time. By the way, to measure ripple you should use AC coupling and increase the vertical sensitivity. Also your 1202XE might be able to see RFI using the FFT function. 73!
Thanks for the review. For general, non radio purposes- my "go box"- I'm thinking the ripple is not an issue. Agreed? If I need to add a capacitor, put it in line on the positive leg?
Hi leftofone, You probably want to correct the ripple regardless of what you are powering. Many devices have issues with ripple. You also probably want to be able to bypass the boost converter when it's not needed to conserve your battery life. Here is a link to a 1 minute video of a project box accomplishing both requirements. It includes the schematic that shows how to hook up the capacitor. It also has links to all the parts on Amazon in it's description: ua-cam.com/video/Ts8prf1N9fM/v-deo.html Hope this helps! Stu AG6AG
@@AG6AG Helpful video, thanks. In my build I'm installing an XWST boost/buck 9-36 v to 13.8 v 20a converter. I'm assuming my unit will likely have ripple and install the same capacitor as yours. Think I'm okay with that plan?
Hi leftofone, All devices vary a bit. I would test the device you are working with to confirm if there is ripple. The Capacitors listed are 50V and "Should" handle the converted 13.8V and store a large enough number of pF to work for you. The capacitor shouldn't hurt anything if you install it regardless of ripple, but it's always best to know for yourself. Remember, every device design behaves differently, so test what you buy before you deploy it. Stu AG6AG
Hi David, I'm assuming you are asking about the XWST. Under our test conditions I saw right around 10mA which seems to be about the same as the MFJ. I typically turn off / bypass the device when I don't need it. Hope that answers you question! Stu AG6AG
Hello Stu, and thank you for the review. When you were using the booster with your HF rig, did you notice the unit producing at RFI hash/birdies on the HF bands? Thank you, Brian, KG8CO
Not at all, but I have a sort of high noise level to start with. I can say that there was no "new" artifacts in the waterfalls and no increase in noise floor. Stu AG6AG
Did you measure efficiency (Po/Pi) of the two? Can you measure the temperature rise of the two, without load, and under load? Both of the above measures look to how much power they use (there's no free lunch, right?), and how efficiently they get rid of the heat that they create.
Stu, I didn't see that you showed what the $60 boost converter ripple looked like under load with no additional added capacitance. Switching regulator circuits usually have better regulation under load - when freewheeling, they can look not so great. Also, is your horizontal sweep 10nS? I'd like to see what they both look like at a slower horizontal rate. Interestingly your MFJ ripple also increased to 800mV when the $60 boost was attached. You might try adding capacitance on the input of the $60 boost converter OR use an actual battery so that the supply side has better transient response, and see if that $60 converter cleans up.
Hi David, Great points! I did actually show the load ripple with the capacitor in place on the $60 unit around the 15 minute mark. The Under Load reading was done without the capacitor but I did not show it as it was over double the unloaded ripple. We also tested on a 12V battery and saw the same ripples for both devices regardless of load. As for the horizontal sample rate... Yes, a slower rate shows the initial pop and the recharge of the inductor, although having it a the shorter time sample improves the response time of the scope samples (just a $350 Siglent). Hope that answers your question... Stu AG6AG
Hi Brandon, I've had it installed on my FTdx3000 since the video but have only needed to use it for about 10 - 12 hours total. I have another one that I use with my FT991 in a go kit but that one has only been out about 6 hours. So the short answer is "so far so good". One thing I have noticed is that when the input voltage drops below about 11 volts, the device is starved for power. This can be seen in all it's glory when the cable feeding the from the battery has high loss (usually due to distance and wire gauge). Once I corrected those issues it worked pretty well for me. Stu AG6AG
Well, not all of them. I've had good luck with many of the products out there, and there's really nothing that can't be fixed with toroids and filters... Stu AG6AG
![Lp. Сердце Вселенной #60 РОЖДЕНИЕ ЛОЛОЛОШКИ [Финал] • Майнкрафт](http://i.ytimg.com/vi/YoR0pAV9FVQ/mqdefault.jpg)
Thanks, Stu, for testing the booster. Last December, I bought the 25 amp version from the same seller for my go box but haven't used it yet. I also bought a low battery switch which would be connected before this device to keep it from taking the battery down too much. As you described, the MFJ has that and other features in the same box which can be opened for troubleshooting, but it isn't as "waterproof" as the XWST Boost Converter. I will purchase the capacitor as you described and keep it in the go box so that I reduce the ripple. 73, Robert
Great! Let us all know how it works.
Stu
AG6AG
Stuart, your test, the capacitor fix, and your comments seem particularly useful for a non-HAM problem. A lot of folks and I own a Suzuki outboard motor. For about 10 years, these motors had a habit of being tough to start due to a voltage stability issue on a wire powering the Engine Control Module (ECM). Anything at all would cause it, from poor connections, to voltage drops during cranking, to older batteries that weren't completely topped off. It was maddening, and for most owners it still is. That includes me. Then, the thought came that we might use a DC-DC boost controller, waterproof of course, and unfortunately the ones tested reportedly created quite a bit of RFI, and now the wavering voltage you described. Well, with marine VHF our only lifeline (156-162 Mhz), RFI is a red flag, and I wouldn't want to test the effects of the "ripple" on an already voltage-finicky ECM. I'm going to try the XWST and capacitor solution, and because boats all have a battery switch we should be able to connect it and forget it. Thanks much. I'll try and report back on the results.
Hi,
I'd be very interested in this. Let me know how things work out?
Stu
AG6AG
@@AG6AG drive.google.com/file/d/1wLdBFEmCt4UGaF6MBOsB1sRpd4KlIQYx/view?usp=share_link
Stuart, I installed the booster, along with the capacitor on the output, and the engine control module on my Suzuki outboard now seems insensitive to battery voltage. This is a big win. I'm getting a consistent 13.75 volts on the output of the booster. Now, I go back over the endless discussions on "The Hull Truth" and other blogs and see how everyone was just trying to salvage the last remaining hundredth of a volt in order to avoid engine shutdown. There simply was no space left on the board in my boat's bilge access for a new box, so I just mounted the booster and a stainless terminal block. I'm not happy about the capacitor connections, which are just pinned under each screw on the output side. Lots of rough motion could eventually break the capacitor wires, so I need a way to connect leads to the capacitor, and that will permit me to immobilize the capacitor to prevent fatigue. Any advice would be appreciated. Thanks again. - Bill -
Good, useful information. Thanks.
You're welcome!
Stu
AG6AG
Thanks for the look at the low cost option. Be careful leaving it attached to the battery for a long time - even the MFJ must be turned off or it will run the battery down after a time. By the way, to measure ripple you should use AC coupling and increase the vertical sensitivity. Also your 1202XE might be able to see RFI using the FFT function. 73!
Great point!
Stu
AG6AG
Thanks for the review. For general, non radio purposes- my "go box"- I'm thinking the ripple is not an issue. Agreed? If I need to add a capacitor, put it in line on the positive leg?
Hi leftofone,
You probably want to correct the ripple regardless of what you are powering. Many devices have issues with ripple. You also probably want to be able to bypass the boost converter when it's not needed to conserve your battery life. Here is a link to a 1 minute video of a project box accomplishing both requirements. It includes the schematic that shows how to hook up the capacitor. It also has links to all the parts on Amazon in it's description: ua-cam.com/video/Ts8prf1N9fM/v-deo.html
Hope this helps!
Stu
AG6AG
@@AG6AG Helpful video, thanks. In my build I'm installing an XWST boost/buck 9-36 v to 13.8 v 20a converter. I'm assuming my unit will likely have ripple and install the same capacitor as yours. Think I'm okay with that plan?
Hi leftofone,
All devices vary a bit. I would test the device you are working with to confirm if there is ripple. The Capacitors listed are 50V and "Should" handle the converted 13.8V and store a large enough number of pF to work for you. The capacitor shouldn't hurt anything if you install it regardless of ripple, but it's always best to know for yourself. Remember, every device design behaves differently, so test what you buy before you deploy it.
Stu
AG6AG
@@AG6AG I'll try to locate a scope- however I don't own one.
How much current does does the XWST use with no load and with a load? Thanks David
Hi David,
I'm assuming you are asking about the XWST. Under our test conditions I saw right around 10mA which seems to be about the same as the MFJ. I typically turn off / bypass the device when I don't need it.
Hope that answers you question!
Stu
AG6AG
@@AG6AG Thanks, I will pick up a couple capacitors at Dayton this week since I plan to buy one!
Hello Stu, and thank you for the review. When you were using the booster with your HF rig, did you notice the unit producing at RFI hash/birdies on the HF bands?
Thank you,
Brian, KG8CO
Not at all, but I have a sort of high noise level to start with. I can say that there was no "new" artifacts in the waterfalls and no increase in noise floor.
Stu
AG6AG
Great as always K6HHW
Appreciate that
Stu
AG6AG
Did you measure efficiency (Po/Pi) of the two? Can you measure the temperature rise of the two, without load, and under load? Both of the above measures look to how much power they use (there's no free lunch, right?), and how efficiently they get rid of the heat that they create.
Stu, I didn't see that you showed what the $60 boost converter ripple looked like under load with no additional added capacitance. Switching regulator circuits usually have better regulation under load - when freewheeling, they can look not so great. Also, is your horizontal sweep 10nS? I'd like to see what they both look like at a slower horizontal rate. Interestingly your MFJ ripple also increased to 800mV when the $60 boost was attached. You might try adding capacitance on the input of the $60 boost converter OR use an actual battery so that the supply side has better transient response, and see if that $60 converter cleans up.
Hi David,
Great points! I did actually show the load ripple with the capacitor in place on the $60 unit around the 15 minute mark. The Under Load reading was done without the capacitor but I did not show it as it was over double the unloaded ripple. We also tested on a 12V battery and saw the same ripples for both devices regardless of load. As for the horizontal sample rate... Yes, a slower rate shows the initial pop and the recharge of the inductor, although having it a the shorter time sample improves the response time of the scope samples (just a $350 Siglent).
Hope that answers your question...
Stu
AG6AG
Any updates? Is the 60 dollar china booster still in operation??? Good video by the way.
Hi Brandon,
I've had it installed on my FTdx3000 since the video but have only needed to use it for about 10 - 12 hours total. I have another one that I use with my FT991 in a go kit but that one has only been out about 6 hours.
So the short answer is "so far so good".
One thing I have noticed is that when the input voltage drops below about 11 volts, the device is starved for power. This can be seen in all it's glory when the cable feeding the from the battery has high loss (usually due to distance and wire gauge). Once I corrected those issues it worked pretty well for me.
Stu
AG6AG
The issue with all the boost units is will they cause RFI
Well, not all of them. I've had good luck with many of the products out there, and there's really nothing that can't be fixed with toroids and filters...
Stu
AG6AG
Unfortunatly the MFJ is no longer available.
Sadly, this is true... My guess is that the schematic is available for this though...
Stu
AG6AG
@@AG6AG Yes the schematic is in the back of the manual. I just downloaded it from the MFJ website.