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Xelectro
Registrace 3. 05. 2021
Radios, RF Amplifiers and electronics
Video
Dave Made 1x2 Base conversion to 2879C.
zhlédnutí 223Před 14 dny
Dave Made 1x2 Base conversion to 2879C.
Xforce Base amp (2x Toshiba Red dot) repair analysis.
zhlédnutí 186Před 14 dny
Xforce Base amp (2x Toshiba Red dot) repair analysis.
LDMOS Put to the IMD test. (MRFX1k80H Repair and signal quality test.)
zhlédnutí 416Před 28 dny
LDMOS Put to the IMD test. (MRFX1k80H Repair and signal quality test.)
IMD, Linearity and 2 Tone test (3cx3000a7 as a Guinea Pig).
zhlédnutí 358Před měsícem
IMD, Linearity and 2 Tone test (3cx3000a7 as a Guinea Pig).
GS-35b (Dual Tube) Full power quick test. (Episode# 7)
zhlédnutí 524Před 2 měsíci
GS-35b (Dual Tube) Full power quick test. (Episode# 7)
GS-35b ( Dual Tube) Episode #6. (Low Power output test)!!!
zhlédnutí 1,1KPřed 2 měsíci
GS-35b ( Dual Tube) Episode #6. (Low Power output test)!!!
GS-35b (Dual Tube (Episode #5) PA Section, output tune!
zhlédnutí 1,4KPřed 3 měsíci
GS-35b (Dual Tube (Episode #5) PA Section, output tune!
GS-35b (Dual Tube (Episode #4) Lower Deck Completed and Tested!
zhlédnutí 652Před 4 měsíci
GS-35b (Dual Tube (Episode #4) Lower Deck Completed and Tested!
GS-35b (Dual Tube (Episode #3) Bias Control board!
zhlédnutí 419Před 4 měsíci
GS-35b (Dual Tube (Episode #3) Bias Control board!
GS-35b (Dual Tube (Episode #2) Input Circuit and Tune.
zhlédnutí 483Před 4 měsíci
GS-35b (Dual Tube (Episode #2) Input Circuit and Tune.
GS-35b Dual Tube Build Series (Episode #1).
zhlédnutí 341Před 4 měsíci
GS-35b Dual Tube Build Series (Episode #1).
LDMOS Repair and Upgrade for Channel Cat.
zhlédnutí 251Před 5 měsíci
LDMOS Repair and Upgrade for Channel Cat.
Electron tube fun!!! How I got started with tubes.
zhlédnutí 1,9KPřed 5 měsíci
Electron tube fun!!! How I got started with tubes.
LDMOS MRFx1K80H Ver.2 Water cooled pallet.
zhlédnutí 1,2KPřed 7 měsíci
LDMOS MRFx1K80H Ver.2 Water cooled pallet.
3cx3000a7 working with NB757 (Boulder, CO).
zhlédnutí 671Před 8 měsíci
3cx3000a7 working with NB757 (Boulder, CO).
3cx3000a7 for NB777 (Official full power video)! 10k on SSB?
zhlédnutí 1KPřed 9 měsíci
3cx3000a7 for NB777 (Official full power video)! 10k on SSB?
SSB Full power test for NB777's 3cx3000
zhlédnutí 398Před 9 měsíci
SSB Full power test for NB777's 3cx3000
Do the boards sit directly on the heat sink?
Needle bender, where should one start if they wanted to get into building?
When you say tsunami I get the vibes of a decent size tube tester for multi band.
I woulda never guessed that was under the lid . Pretty neat . God fix ,, another one resurrected on the Doc Brown lab table 😎
Great work ! I had to play with them primary taps before. That clean for a unregulated supply. Got a real nice filter cap. The last base amp with transformer I worked on was a old dave made. that was a 4 pill. had 2 transformers. was not biased either. It kept going to shop to shop. problem was them so called 50 amp bridge rectifiers. The oner talks a lot on it. I did have to tune the box after i biased it a tad. was a big box so i used them brass tube caps and tuned it out. I took out them old bridge and put one of them 200 amp ones in. both to bottom with thermal paste . Re did power wire to 10 AWG OFC . it's doubled up. 2 hot/ 2 ground from caps to amp. gained a few watts . Feedback I got ,It sounded like new amp. was class c now biased 4 pill. had to put in new relay's . kept losing RX . 73
Nice little amp
Very nice!
👍
Those look great . Look fwd to seeing some of your builds using those !!
Amazing, thank you
I think they will work with a Byrd 43 line section. That HALL sensor can do DC amps with just clamp over wire like the AC meters do. So many ways to set them up. Some of them China ones are total junk. 73
Yeah thats exactly my plan.
Can't wait to use them
Awesome!
Hard to beat the old school Dave Made amp ! Thanks for the video
Nice work as usual
Thanks!!!
I like the old Dave made ! Nice transformer ! I was wondering what 2879C would look on scope and spectrum test . I have totally re done that Xforce base amp. 2X4 . I converted to 1 MRF 455 driving 4- RFP 2SC2879. It had 2 PP 80 driving 2 PP 100 . all 4 pills blown and was class C . was a nice AB bias when I got done. this was years back now. And them China 30 amp SPMS hit the trash can. They will NEVER do 30 amps ! I changed so many of them . They just do not last . 73
Original amp was built solid, with good parts and metal clad caps. However when it came to sideband all it had was a sideband delay switch but the class of operation was class C. I guess sideband wasnt very popular 30 years ago and nobody cared. But I am actually really pleased how this amp turned out and how clean it actually became. ~73s
Nice old amp ,, good job as always 👍
Thanks Dallas!!!
Thank you!! Great work.
Thanks!
Nice old amp. That bias looks too low and maybe due to lower voltage and the sag under load. changing bias diode and resistor should do the trick. if collector voltage stayed at 15 V the bias may be ok. I could not see what diode they used. but easy fix. ICA has better transformers for replacement if needed. has taps to select voltage . Also a better bridge rectifier can help with sag. mostly on 6 pill and bigger. that just a 2 pill. Sometimes a bigger filter cap is needed. ICA has some great ones. But on that amp the cap is biganouth unless it's bad. I scope test DC supply for ripple voltage. A weak cap really shows up when putting a load on supply. As long as not driven hard that supply is just fine. That splatter will clean up a lot with bias fix. It will get real bad with 120 HZ getting in from weak cap. not the case hear. I re did a 8 pill like that . was a blue one with pp 100 pills . so much work. does 2Kw PEP now but tad dirty. 1.2Kw clean power. Thanks to ICA transformer and caps . I get my 200 amp bridge from another source. Tony has been great ! 73
Its already been replaced. There was a wrong diode in there. Customer doesnt want to change a transformer just make it sound better on SSB. Otherwise its running now alot better then it did 2 hrs ago.
@@NeedleBender785 it is a 2 pill. no need to go crazy. just the bias fix is just fine. I find it better to control radio drive power than use hi/low switch on amp. Today's radios do that very well.
Awesome video! Great info as well ! DO EET!!!
Thanks!
is that a TC004 Thermal Imaging Camera ? how do you like it ?/
I like it alot. Sometimes its a bit laggy as far as moving around fast but not too bad.
Thanks for the video, Great suggestion about others showing the results of their builds not to bash but it'd be good for the hobby..,.73
Thanks!
Thanks for the video. It would be nice in future tests to show a peak hold harmonic display out to the 9th?
Its something I can look into. But from testing amps before I can tell you that its sort of a waste of time. 3rd and 5th harmonic are what we normally see in bad amps. Unfiltered LMMOS being the worst and its always clearly visible without peak hold mode.
Very nice work Tony . 73’s
Thanks!
Wow. That's a lot of punch for such a small platform. ✌✌
Looks great ! I was wondering how the 2879C would do on IMD test. When tubes biased right and tuned correctly they very good on SSB for the IMD test. I run FT8/FT4 WSPR all from WSJT-X software. you can decode with that program for the HAM bands . No licence needed to receive only . JS8-CALL and FLDIGI are outher programs for digital modes. You can use them on CB as long as legal power levels. Even SSTV . I sent and received pic's from NY to England on SSB CB. just watch them amps on digital . keep drive way down. It is the high duty cycle that heats them up. 73
Yeah FT8 is something I was hoping to learn sometime. I am actually an extra class but when it comes to HF its voice only for me. 73s
@@NeedleBender785 Me Extra as well . Once you get settings right FT-8 is easy. Lots of videos on youtube. FT-8 is also on VHF/UHF . I just did FT-8 on 6 meters the outher day. 73
Careful, you'll end up building boxes for FT8.
Haha!
Are you willing to build for the public?
I do build custom order boxes. Mostly high end stuff. Majority of my builds are Tubes. But I do build pretty much anything you want. My stuff runs about 50% pricier. So if you are looking for best bang for the buck look elsewhere. Otherwise sales@xelectroshop.com
I’m late getting to the video ,, great work Tony !!
Super awesome to see a 2-tone IMD test for LDMOS, thank you for sharing! I tried connecting 2 separate pallets with ART2K0’s (Ampleon) together using a 1:2 ferrite combiner like you show in this video, and I measured -20 dB of 3rd order IMD using 2-tone audio test at 2kw PEP which agrees closely with your results. I totally agree with you: -20 dB is not a good IMD result and will definitely cause some unwanted audio splatter, especially with SSB modes. But then I tried connecting 2 ART2K0’s in parallel on a single, unified pallet just like the ham radio guys do (no combiner is used because drains of FETs directly connect together electrically using a 9:1 transmission line transformer). IMD was much better, -33 dB for 3rd order IMD and -42 dB for 5th order IMD with 2-tone test using 2kw PEP for pOut. Connecting the drains together electrically in parallel vs. using a 1:2 RF combiner was a big improvement in IMD that I did not expect, but glad I tried it. The only downside is the higher cost of buying a second FET which is an extra $226 for ART2K0. The extra cost might be worth it if a super clean signal is needed, especially for SSB customers.
So with 2 devices you are basically operating one device at half power. And thats what my test was showing, when you get closer to 1kw PEP per device the IMD looks alot better. 2kw out of a single device is gonna be terrible.
Pretty cool, I can't wait
Thanks!!!
Bro thank you for explaining each part and it's job. I am learning to build and repair tube boxes and this was a gold mine ty bro
Let me know if you have any questions, always here to help. sales@xelectroshop.com
Nice testing. I did notice that LDMOS does have some IMD at full ratings. From what testing I have done dropping to 50% of rating cleans them up a bunch. Tubes when biased correct are buy far cleaner on SSB. Other FETS like IRF520 get quite dirty at power ratings. When you go back to BJT like 2SC2290 they pretty clean at rating's bias and tunes correctly. Something with FET transistors on SSB. now go to AM/FM/CW they much better . I did notice running LDMOS at 50% power on SSB they run quite cool . 73
You pretty much summed up my video in your comment. Thats exactly what I have found. To get 30 or more db of 3rd suppression you have to get to 50% of rated power. I am gonna do a 2sc2879C test here in a bit and see how that performs. Thanks for your input.
Interesting, do you think the results are typical for that type of ldmos transistor?.. Thanks for sharing....73
I would say absolutely unless you turn the power way down. To be completely fair I am using a cheap Chinese power supply since there are very limited 65v power supplies. And there is a chance that partially its caused by the switching power supply voltage ripple. But I wasnt impressed by any LDMOS performance when it comes to signal quality, my design still outperforms alot of others but i am not impressed with the results. Now my 3cx3000 did fantastic if you watch a video from a few weeks ago.
@@NeedleBender785 yes absolutely -34db awesome Look forward to seeing more in the future
Very cool. What do you use for your rf sampler that feeds your scope and spec-anny?
5000kw Bird RF Sampler with a built in attenuator.
When does this LDMOS start compressing? Have you tested it on FM yet?
FM is a constant wave basically CW and its totally fine. Third harmonic is more the 55dB down. AM has similar flat toping as well. But SSB is by far the best test for any amplifier especially designed to run on SSB. after about 1200W PEP signal starts to degrade and after about 1500W it really degrades. Most people buy these to run 2Kw.
@@NeedleBender785 So, it consistently outputs 2.0 KW on FM. I'm from Europe, where we mostly use FM or SSB. On FM, you could reduce the bias by a quarter or even run it entirely in Class C mode; it shouldn't make much difference. As a driver, I have a Hermes 3 SDR transceiver that puts out about 10W.
@@fnordist On FM i wouldnt run this device above 1kw for an extended period of time. The ammount of heat it generates is huge. I would say 1kw is the most you can get and it is very clean with very minimal bias probably class B.
An you tell me who makes that 40kv 40amp blocking capacitor and what part number is please?
So the capacitor that was in that original video is no longer used by me as the datasheet doesnt cover the frequency of operation. I never had any issues with it but decided to switch on my own to a more robust RF rated cap. This one is a Russia transmitting capacitor with a KVar rating of 90000watts. (reactive). www.ebay.com/itm/275746653186?itmmeta=01J2EAZ4DAASN495C57PCSRGSX&hash=item4033c80402:g:8~MAAOSwJ1xknrlr&itmprp=enc%3AAQAJAAAA4DYuwmUuUf9V3WPCLNib5fEOWOEBjyLRxunA8nak8GRy3ih8z8HHFrv6boryK1jsL%2FEP9QlhQLmM4fP2fUWPLWLNdH6QiYJ3JSF447BeJ8HLmRM2bi4Zuvz%2FCizws4qLPArKh72bqzoxfbME%2FFbFMTednkyJOj1Odw2AAigFxxevbaRYtvA4lIByPB3paSCQt9T2CtT06WT2xrnk8kfWli8rp2%2B%2BbGkqUYqpC95hZCv%2FAIhA74h4GdaQZXx2Ow4SJnL2ejOf0CBrYymAE%2BNmV1mFzvXHaxdRsZO3Mqp4sBms%7Ctkp%3ABk9SR97G_MqTZA
Fantastic information and demonstration it'd be interesting to see some of these popular Amplifiers being used today on same test...of course without names or finger pointing more of an example of what's commonly being used, thanks for sharing
Going to do some transistor amps next. And again testing my own builds. When you criticize your own work and show when something is good and when its not. It forces the customer to ask their builder the same question thus raising the bar of product quality at the end.
That a great way to do that PTT keying. also works with radio that does not have PTT line. use foot switch to key radio on 1 jack and amp on outher . great for SSB. Also can use as a isolator for old tube amps like Collins ETC that have HV on PTT line . The last one I made was for a IC 705 radio that does not have 12V PTT. I used a opto isolator with small relay. works great . now someone made a bord for the IC 705 that fixes that issue. Icom does make a EXT one put $$ . The new board does USB C as well. Buy swapping out jacks you can easy make a Stryker radio or whatever you want to key a PTT line AMP. I did this inside my Cobra 2000 base radio. small relay inside and RCA jack on back. Great SSB ! 73
Yeah thats exactly how this one is wired. A PNP transistor keys the main relay with under 1mA of signal current. The main relay then keys up the 2 ports wired in parallel.
@@NeedleBender785 Very good ! I figured a PNP or opto-isolator . I tried a small mos-fet but got stuck on a whole bunch. just too sensitive. Their is a keying board we use on repeaters to have delay on keying. like the PA section key first then the transmitter and reverse on un key. has adjustable delay. I thought about using that for amp keying but never got to it. What you made gets the job done. This saves the TX relay a whole bunch on SSB. I use foot pedal myself to keep hands free for like PC typing of a log .
Good deal ✌️✌️
Awesome! Needle Bender 785, it was great chatting with you today WR0546 MN.
@@user-vi6lw8dx5f Yeah thanks for the contact.
Awesome work as always in the Doc Brown Mad Scientist Lab !! My setup will definitely benefit from that Thanks NB-785 ,, looo fwd to putting it to use !
Dallas will put it to good use!! 73s !
You know that’s right 😎 Thanks man , and 73’s
Very nice.
Beautiful job!! Very impressive work for sure!!
Very nice Tony Look fwd to the new build in your Doc Brown mad science lab !!!!!
nice work. That SB 220 is clean as well. A clean signal gets out better ! Peek watts means nothing if distortion . Nice showing the wave forms. Starts with a clean radio . I had some tube amps to fix that where just driven too hard to long and tube flash Then lots more parts burned up. Watch for them Cheap China tubes like 811A or 3-500Z .They known to flash over. get good tubes like Penta Labs or RF Parts ones. Replace 811A with Penta 572/B . Some junk 8877 China ones on eBay . The Russian tubes are real good and getting hard to get for some. 73
Penta Labs tubes are made in China, RF parts are made in China. This might be news to you, but just because the company selling them is in America, doesn't mean the manufacturer is. I guess you can keep believing those are American tubes if it helps you sleep, but they're made in China.
I wanna incorporate a 2 tone signal in all my future builds just to show what the amp is really doing with the signal. Otherwise lots of IMD splatter will make any watt meter happy.
Real cool Tony , you have my 100% attention, keepem coming
Thanks, looking forward to implementing 2 tone for all future tests.
That dude is cool
I almost hate to hear that will be used on ssb. Awesome amp for sure✌✌
Thanks. !!!
That's crazy power. Great craftsmanship. ✌✌