110 volt AC conundrom.

 110 volt AC conundrom.

I needed some power supply of 110 volt ac for a valve device i recently acquired. Its need was 110 volt ac 20 watt. As all valve radio devices have pure resistive  loading part . So, they require more current capacity that required in start-up etc.

Well we in india have only 220 AC line. We find lots of auto-transformers for many nintendo and other consumer product. They work for them. i can also use them. My problem is i do not want to have live wire at any part of my instrument. That is because my small kids also loiter around my shack/office room/work room and they touch and help me also. when we are testing less worry we have more we concentrate on the work. 220 ac has very small thevenine resistance that means it can source lots of current.

I once had from junk an auto transformer having 220-110-0 . i did not like because when i put my device on it that ruined my fuze. thank god. you can see that in my vedio. link is here first vedio. part 1 

and second vedios is part 2 .

Then i did thought well 110 volt is just half of our line voltage why not put two transformer back to back and get. I thought i got the solution and rushed to the shop. bought two 12-0 , 5 Amp and 12-0-12, 5 amp transformer. With mischievous smile that i conquered my problem urgently wired and the transformer. it cost me 170+170 =340 Rs approximately 5 us$. i said ok as could not get the 110 volt ac transformer. Then made it it gave me around 116 volt ac. i said ok now lets test my American soldering iron of 30 watt. If that work then sure my device with 20 watt power will work. Put my soldering iron and it loaded started to slowly heating up. i said ok, test the voltage and it was around 72 volts.

See my notes. putting here as pictures. Then, i thought that my device is not getting enough source current due to the inherent high resistance. So , i need more current to push. So, on next day i bought another 12-0 , 5 Amp transformer. paralleled it with 6 ohm combiner. Thinking was that it should see small resistance going toward the output 110 volt ac transformers and high resistance path towards other transformer. see 6+6 ohm path and zero to output transformer. 

Then i parallel 12 ohm to get 6 ohm as could not get 4.7 ohm. i think this idea is good but you need some small 1 ohm resistance that will be enough.

well what happened, first i said compare my result with only one transformer, 12 ohm. it gave me No-load 93 volt. good enough. Then with 6 ohm resistor i got 107 volts ok. but on loading 30 watt soldering iron it turned down to 43 volt ac. Why this happening because we have finite VA that wattage and we have internal resistance of the transformer so when you need more current then voltage reduces and you do not have enough umphhh. EMF.

Then i paralled two transformer. See the diagram. 

i tested and it gave 113 volt ac no load and 57 volt with 30 watt load. As last try removed the resistor by bypassing it. so it hold me around 77 volts and the iron was immediately becoming hot. which means it is getting enough current.

Despite having this 3 transformers i am not getting my result. Why why why. i did everything to reduce the thevenine resistance to get more current ?

i paused, if i had asked someone to make me a transformer then in 510/- that person might have made me a brand new transformer. what i will require is 110 volt act with 500 ma to 1 amp current capacity. it might be big. 

I knew that my thinking is right, my problem is thevenine resistance. i do nto want to use 0-18 volt ac in output transformer. As it will increase the no-load voltage and then reduce it to working one still it will be not constant 90 volt, the required minimum. What a conundrum.

What i have not tried. Looked at the setup. Not finding solutions. i gave up. solutions is simple i have more then enought VA as input. Why i am not getting the enough current and voltage as per plan.

Paused. let it go. Then in the night time when i was closing down my room then looked at other transformer. Ohh, the 12-0-12 volt ac has thinner wire compared to my other jumbo 12-0-12 5 amp transformer from different company. Ohh, it seems i found the solutions. I need to replace that big transformer with this tiny transformer.

RULE OF THUMB is that output transformer should be thicker wire then input transformer. 

Lets see.

I tried one of my old very meaty transformer having thick wire. it produced me 120 volt ac. No voltage drop. Then on loading 30 watt iron it got me around 82 volts. That means i am nearing the range of 90 volts. I am going on right directions. If i use these two big beefy with large dia-meter wire i am sure that will work out. as 20 volts loads less. and minimum voltage of 90 volts i am near about. If my shop had those tranformers i might have solutions with less cost. Anyway i will be using these power transformers also in other projects. It is not wastage.

Meanwhile, the original source, the friend who got me this GDO has promised that he has a spare power supply transformer and that will work. waiting for it.

I can say it was partial success because, theoretically i was right in getting the voltage, testing it. But, practically i invested 3 tranformers but my choice of half voltage was wrong i should have chosen 18 volt combinations, 0-18 & 18-0-18 vac with thick wire. lower voltage we go the wire gets thinner.

RULE OF THUMB  choose higher voltage transformers. Less loss in flux, hysterisis, less internal copper resistance.

RULE OF THUMB Second thing, use both transformer with thicker wire, that will reduce voltage droppings. If you are planning learn from my experience. VA ratings should be atleast 4 times of the load.

problem solved. hope this helps you out. It is possible to use this configurations for low power use. Please always avoid auto-transformers. It has shock hazard as its directly connected to the mains AC line. It can source large current so device if not fuze protected or voltage current sensitive, it will be hard to it.

so, wheel is re-invented but it has puncture. so, waiting for the spare wheel.

Third vedio of working power supply ok here is the first working https://www.youtube.com/watch?v=jLmvUZ_2dTo

morse code radiotalks 2

In this page , we will start our journey to understand the morse code.
how it is made, why it is made, what is science behind this code.
how code is actually made and from this code how coding and decoding of inforamtions is done.

So, the vedio is the direct introductions to the morse code.  key words are
 https://www.youtube.com/watch?v=zHzNP72n5vM
morse code
dot, dash, space,
alfabets, numerals, punctuations, pro-signs, short forms, grammatical symbols.
coding and decoding.  morse key. hear it write down pen paper.

By listening to this short durations 9 minutes vedio you enable yourself the above concepts. why and how code is created is given in the end part.

So, now what ? is it end ??? no, it is beginning. morse code is sound. have a good start. easy regular and everything will be fine.

Next vedio we will learn each alfabets of these codes. till then 73. by the way this blog is always under construtions. whenever new nice words things comes i put them, re-arrange it.

Lets learn,
first vedio is  ET IM AN link is https://www.youtube.com/watch?v=Be8wy9iGU-I
 second vedio is So DU GW KR link is https://www.youtube.com/watch?v=TfGxzy8F52w
third vedio is H BVJ C  FLYQ PX Z link is https://www.youtube.com/watch?v=JnNB6jd1mjM
Fourth vedio is
Fifth vedio is about practising the character so far we learned. https://www.youtube.com/watch?v=TnTcp6gmqTQ . Download the software. practise listening to it daily 10 minutes morning evening at your convenient. That will be a good help.

MORSE CODE CHART

1, E T
2, I M    AN
3, SO  DUGW KR
4, H BVJC FL YQ PX Z

MORSE KEY

INSIDE MORSE KEY

familiarize.

radio talks 1

https://www.youtube.com/watch?v=8aZuB5DK7zy

click here  for vedios https://www.youtube.com/watch?v=8aZuB5DK7zY

Here is the transcript of the talk.

My name is indrajit, i live at the foothill of mount girnar. i am farmer, advocate and i am radio amateur with call sign VU3INJ. i also write a blog. you can find link in the discription. vu3inj.blogspot.com.

For me the inspirations of making this small vedio tutorial is the KE0OG, Dave Castler. he remind me our elmer vu2dev, guru dev.

There are many information's, vedios, books, talks inspiring us to be radio amateur. there are many vedios on how they enjoy their radio hobby and their achievement or special technical subject of expertize.

From my experience, the radio amateur journey can be classified in the follwoing time-line segments.

First is ---> inspiration to be ham / radio amateur and then actually contacting a real  ham. Getting a demo in club stations etc. First step is inspriations, many peoples are doing great work on it.

Second is :---> getting ready for the asoc , ham radio examinations.
fill the forms,apply for radio examinations,get the study materials, preparation for exam, giving exam and finally declaration of the result.

after this i call a
Third stage is :---> If successful, waiting for the license this can be month or years. There will be anciliary process of police verifications, fee and other correspondence.

Forth stage is ---> Actually getting the licenses in your own hand.

And fifth stage is :---> procuring the instruments.radio equipments. the biggest pitfall is here. You need to decide. What choices ?  make your own radio instruments, buy cheap chines ones , american kits, or japanese commercial equipment. this is a big thing.

Advice from my experience is go for commercial equipment. over the time save your money over the years when you get around 35k-50k look for fresh rigs which suits this budget ft817 and many mores etc.

Do not fall into the traps of homebrewing. although i am a big homebrewer and learned at great cost of money and time.

Whole point of all these talks is getting into the air and communicate.

in india due to red tap and securities issues the license issuing process is very very slow. nothing can be done about it. bear it.

Be on air. that is true ham radio. being on the air should be our motto. All other steps are necessary evil of the system.

be on air day after day and then you will really enjoy the friendship and comradary of radio amateurs.

73, see you on AIR.

cw transceivers

Problems:- 

I enjoy home brewing. When project  takes too much time in development , board is finished but i do not have other necessary technologies, to wrap up the things i box them up as it is. later on, when time comes ripe, i use these boxed-device after lots of changes. I am rejuvenating one of that transceiver project. That was made few years back. That was never tried on air nor their air worthiness checked.

Our ham station must have some air worthy transceiver.

On impulse of coming to air, few months back tried to make the 21168kc xtal based cwtx-dcrx transceiver but the xtal was 3rd harmonic one. It was not usable on 15 meter and did not liked to use it on the 7056, So i tried the 21096 in the same platform. RX was good sensitive but the irf 510 is not producing enough umphhhh.  Need to redesign the cw tx chain with 2n3866, 2n2078 etc a big work. not doing. abandoned the 15meter for now.

Then i remember in last to last lamington road electronic market, mumbai visit i had bought the 10 number of 3686 kc xtal.  I placed this 3686kc xtal in this modules and there  was RF ,light in the lamp load. WOW.  It might be producing more than 2 watt RF power. workable. This RF power can drive external linear. good. or it should be usable for local com. hope so.

I am becoming old without any contact. Story can be depicted " unused old stock but brand new in package". he he. Why we should re-invent new new platforms for each receiver and transceiver. I am really tired of making separate seperate receiver, transmitter, transceiver for different different bands. A thought was puzzling me, can't we make something that is workable, usable , reproduce-able and worth every cent of that dollar spent ? This  trx making is costly, time consuming, tedious task.

We need one unit with 3-4 bands, even if it is xtal based, DC receiver and CW / DSB transmitter. We must have at-least 2 to 5 watt. this can be put in small box ( samilar as MTR3-B ) and an external 20 watt linear for reliable communications.

Solutions:-

There must be some solutions. Then i searched my xtal storages boxes. i found this 6 xtal sets. All these are in ham-band. and does not fall into any popular crowded net.

meter band =  tx freq crystal = poliakov rx freq crystal
80 meter band = 3686kc = 1843kc
40 meter band  =7159kc= 3579kc
20 meter band= 14318kc=7159kc

So with one cw tx board, band switching and using the poliakov dc receiver using sub-harmonics oscillators i can make three band portable transceiver.

Good idea.When you are making new device, Plan it right as time is finite. Make airworthy, use whatever you have, operate on cw ,then modify for DSB fone. RX front end should have good band-pass filter. there should be wide/narrow AF filter. there must be RIT. Easy tx-rx change over. There should be RF-indicators. And VSWR antenna tuning. side-tones makes it perfect. just have a look at vk3ye.com and youtube for his work and idea in cw qrp.

So work is in progress when its finished will reveal here with a different write-up. 

And yes, i will be QRT with twitter, facebook social media . also not recharged the mobile-fones internet as no work no money due to corona epidemic.

Straight keying morse is a very tiring work so, i will make arduino automatic cq caller. cq cq cq de vu3inj vu3inj k. Please scan the band. you might catch me on 14315kc, 3686 kc calling cw. Send the SWL report and i will reply with handmade QSL card. i will reply very very short "ur rst 5nn bk hw cpy ? "
73
vu3inj
indrajit.
click here to see " 3686kc transceiver " on youtube.

how to do cw qso ?

here is a image i got from net.cw4u.org

have a look. and also visit at cw4u.org.
Enjoy 73
cu on 14.315 Mhz cw, 3686kc

QSK

What is big deal, you flip the switch and from transmit you are on receive mode and vice versa. True for the SSB or FM transmitter. The PTT switch do it very simply, but here in the CW transmitter lots of things has to be switched on and off for receiver to transmit  in various stages .

Any new home-brewer for him/her the QSK is a biggest hurdles. as they do not know exactly what is going on between receiver to transmitter handover. Lets understand what is happening.  Jump to conundrom portions.

You may first listen my bablings please. As my transmitter were built as a stand -alone unit thus they were not compatible with the receiver sections. I used them as a stand alone devices and was not testing their air worthiness so did not bother to do anything or make them compatible. I enjoyed making things for myself. Time passed on. Lots of things changed. The fuckers bitx failed  and i am back into the cw dsb game plan. Now all those small QRP transmitters needs to be put on air. So the re-inventing the wheel of qsk.

Have a look at these ckts. a single transistors is used as switch. It is simply keying a tx stage. general purpose transistor BC547 keys around 100ma ,good for single oscillator and pre-driver stage or for driving a relay. This served me well. Like it. If you need more current then 100ma use BD139 etc heavey duty, heat sinkable transistors.

Now, I tried to make transceiver from tx and rx modules. I have observed that, when you are putting   rx tx modules in a single cabinet box, the Rx Stages comes near the heavy TX RF fields. This will create the havoc on receivers. So, you got to put the tx modules and receiver module in their respective small metal enclosures , well shielded from each others. Use the plenty of metal separations sheets wherever possible. Use shielded cables for interconnections. This will help, cope up with each other. Putting RF ckt in small small closed environment / boxes makes it neat and clean. in long run the dust does not accumulate on it.

 
There is a qsk ckt given in the ARRL  Hand Book 1978 ,gifted by Guru DEV, vu2dev(sk).

Design element
Important thing to SEE is R-C time constant (the time delay ) how much the relay is hold before it gives the controls back to the receiver.  In cw there is spaces between the each charactes and dot dashes so the ckt should remain in the tx mode even if the key is not down for space time. This varies with operators speed. Hence a variable pot is used to manage the delay.

when is key is pressed the Vcc line is enabled to the electrolytic capacitor, which is connected at base of relay driving transistor. The transistor immediately switches on. Relay is switched on. The capacitor retains the charges and slowly discharges through B-E path and the variable resistor.  To switch on a silicon ransistor 0.7 volts is needed. So this capacitor due to its charge reservoire keeps the transistor in on stage. when capacitor is discharged it switches off the transistor. This creates the time delay.

Here is LIBRA80 ckt  Have a look at this website https://www.qsl.net/sp5ddj/Libra.htm. You may find plenty of functional home-brew projects there. I will try to imitate his QSK which is similar to ARRL handbook. I keep all the ckt in blog as this becomes my handy resources to look and compare things for design.

 

In this conun-drum there are few issues.

a)      CW transmitter = keying. oscillator /driver PA. antenna change over.

b)      RX  = Antenna change-over, protecting the RF input stage from desensitizing, audio chain muting, side-tones generating, shifting of VXO/BFO frequency for 600hz shift / RIT.

c)      Tune provisions, indipendant of QSK ckt for matching Tx and Rx frequencies.


Any Simple well designed switch over circuit can over ride all these problems. what should be characteristics ? There should be time-delay for matching up the CW speed . on keying TX should fire up  and  receiver should immediately go into protect mode. If you do not do it fast the RF inputs goes to RX front end and destroys and desensitize it. when morce key is up for space at this time rx should not be enabled because there will be another possible key push coming after the space time. So, it should be protected otherwise the quick relay change over will make very hard and annoying to listen to. If on qrp rig ear-fones are used see that there is no loud-thumping due to change over audio blasting. If there is any agc-line  you have to make provisions for it. In ill-designed circuit the relay chattering takes places and that harms a lots of things.wear and tear of relay happens.

Solutions are-

There are many ways to do RX-TX handover.

First is - Simple manual switch, this will change-over the all the modules Vcc. one connection of (relay )for antenna, hand over to rx and tx pa side. Another line for the tx/rx Vcc. thats it. 6 pole switch or 6 pole relay does the job. Many homebrew xtal controlled transceivers use this method. simple effective. you need to provide for sidetones otherwize its good one.VK3YE has done it and you can see his vedio of 30 watt cw transmitter.

Second is:- Full qsk everything is selected with proper care, very complex circuit board is needed. Many commercial transceiver does have these plan.

Third is :- Semi-automatic qsk, here muting ckts, tx-rx antenna switching with relays, Vcc etc is done

Fourth is- for QRP only a diode switch over, rit and audio mute is done. no electro-mechanical devices used for antenna change over. antenna is always connected. good for qrp power only.

Fifth is:- if you are using the microcontrollers , all problems solutions can be implemented in the software. here cw keyer,  automatic cw calling etc can also be implemented. using little bit of silicon brain makes our simple transmitter at par with big guns.

too much blah blah, lets do it.(to be continued ...)

11 april 2020. Given below is link to vedio. I have used manual mechanical switch as qsk. very very rudimentary and usage is deprecated, but at least it enabled me to finish up the "bleeding long" project into a logical quietus. Due to lock-down the Relay is not available. So from my junk-boxes found a working DPDT switch from a long forgotten board, dusted it, cleaned it and tested . Now cw tx is working but very clumsy and inconvenient to switch on and off. 

Have a look at this finished setup        CW Transmitter 1 minute vedio is here, click this link. 
 

DC receiver march 2020

The corona blockade has forced to me to do something worthwhile. If we are able to do even then do not fulfilling our dreams  is not a good thing. I wanted a receiver for my 14.318 mhz xtal Transmitter. I have one good  single frequency superhet receivers based on RM-96 derivatives but it needs to be aligned and fixed and nothing ready made.

I looked into the junk box ? what i have. few unfinished junked DC receivers and one un-finished superhet receivers ? any worthy candidate. first and foremost criteria  a working tested modules. because i did not have time and patients for new RAnD.

Here comes my rescue an old "superhet receiver module " where mixing stage somehow did not worked or may be i did not make the good filter or first IF amplifier was too much bad. I used feed back and all short of gimmics (farhans copy) but fucker did not work for me. Finally dismantled that RF amplifier. Removed the 10 mhz xtal filters. Removed VXO crystals. You can look at that module some pages back.

I had removed the audio amplifier, so found another working the ic LM386. I was heating up the ic oscillating up etc. removed it , put the good air, cleaned up and low behold no motor boating and no noise. Then put the separations shields. These are gimmicks/witch crafts but it works. After putting these copper separating shields everything remains in their boundary ? he he.

vu3inj receiver.

Then finally after two - three days soldering and using the good smoothing calming words. the boards is ready with their damsels. Size is very small. See the ball-pen. The women are beautiful. Once our late rev. guru dev ji (vu2dev-sk) had remarked me about my putting the ckt with damsels. I smiled back.

There should be no oscillations, motor boating. There should be good filtering of audio and RF. there should be frequency stability.  Everything should be tight coupled and nothing should be loose. Put it in the good mechanical sturdy box.

RX has golden finger test. When you do not connect to the signal source, all gain AF at their maximum and there should be no big noise. There should be mild hissing when you listen very near to the loudspeakers. Now, go away from loudspeakers. Touch the Finger to the input jack or small 1 foot wire antenna and it should start roaring and there should be high noise. Then you have good noise and good gain in your receiver chain.  This concept of using a xtal filter for a single frequency receiver is boon for early stages of RanD and point to point communication with dedicated group of friends.

As of 4 april 2020- fixed up the QSK but it seems, it reduce the gain. May be attenuating and increasing the noise floor of the receiver . disliking it. lets see that can be improvised later on. needs to be boxed. found out the noise issue, input 100pf removed to 0.1mfd and signal level increased, it over rode the noise floor. hmm.

If i can use the 7812 internally then i may use the 35 volt power supply itself. This tx chain dose not need more power. just 2 watt. means 300 ma at max. tomorrows deadline, no use of internet but just use the time to fix up relays trx and put the beeps. enough is enough. power supply is still a problem. with peak 35 volts dc input 78024 ,7812/7805 will NOT be able to handle. I needs to go for the transitor for a first drop and then regulator will think of it.

On 05-april-2020. fixed up everything called up a friend vu2exp. due to lock down the qth setup is locked up and living at another qth. ok ok. so thought of checking whether rx is working and can cope up with the tx power.  have a look at my 1 minutes YOUTUBE vedio  20 mb test set up is working click here.

As i am fixing up RX in the original tx box which was only for the CWTX chain. little bit of cramped space.  As this is copper plane its rock-solid. Ohh i have to tune it also.

spart 152, M0DGQ

Now, it needs to be boxed and fixed in the cw transmitter box with all RF change over , side tone controls. wait for it.
Thats it falk, here i am re-re-re-inventing the wheels.

Corona and free time

corona and free time.
i was passing through the lock down of the society. What to do ? well i thought why not finish up some project in this free time created by the corona virus epidemics.

Ok, heated up the soldering iron. Humm lets me put a delta loop for the receivers. Soldered it then suddenly found that my soldering iron is not heating up. It gone kaput. look how innocent it looks. Tomorrow morning i have to goto the shop and find the coils as well as the soldering iron. This was a very nice one.

Then repaired the power supply. After a more than a years silence , i have forgotten where are my small and big instruments and all those things. What i am dooing.just putting back my linear of 15 watt and 20 watt on air. i need to box it finally. Each time i use and then store and use, requires tinkering is a wastage of energy. So, box it. non-use then pack it clearly.
27-03-2020


I revamped the linear , boxed it. It gave me the 15 watt RF power when i used it years ago. Fixed up the dipole wires which were handing , bound it and seen the coax for possible corrosions and loose connections. NO. looks goods.
Finally on the forth day of lock-down i tried the SMOKE-TEST. Then  hesitantly put the power supply to exciter and linear. No current consumption. No RF. Sucks.  Linear seems to OK, there is no shorts voltages are ok. fine ? idle current ok. 100 mili amp. Where is problem ? exciter is a trusted one, and i felt there is some loose connections. Hmmm, tomorrow. will do it agains. Something is wrong will fix it soon. Got plenty of time.
Sunday- ohh today is sunday. Every day is sunday. In the morning had the darshan of hanumanji. Then day-time thought of doing the repairs, as my eyes needs lights and spectacles to see clearly. Tested, First IRF510, greased with old heatsink material. heatsink bolts tightened. All bolts unscrewed. Seen for loose joints. Etc. 2n3866/2n2219 is working good, heating up. IRF510 olso shows current variations on the bias preset variations. earlier i though it might be kaput. Then went back to tune buffer stage, it had voltages. switch is working fine.Then finally to source of Rf , xtal oscillator. Hmm , it is not showing the CW note in receiver. Then i removed it. put on the 12 source, tried to hear the CW note. It was there but buffer was not showing any power increase. Then i was touching the transitor and the emmiter follower was very very hot. Hmmm, the classical problem. Removed the BC547b and the CW note was bit stronger. Resoldered. Connected. There is RF power, but how much ? undetermined. After testing the linear i will know whether its worthy of putting on the air.
30march 2020- changed the faulty preset, replaced with 2k preset. But connecting wire broke replaced. When we are making the modules, it should be housed in a a seperate box to save from the dust and all other problems. As this was first made transmitters, i did not know that. Now, every small modules has to be put into its own shielded box and use of connector wires to easily connect and disconnect. with time we progress. Anyway it is once again starting working. On dummpy lamp it shows true brightness. ohh good. But, will it be loading the dipole antenna is a question. Hope,wire is ok. Need on air testing. Tomorrow. I know it can punch a hole.though india. want to make two frequency xtal 14.000 and 14.318. will try 14.005 for cw.  It needs a suitable poliakov receivers as it is cool one or may be other DC receiver. Lets see.
35 volts suppply becomes 27 votls with around 850 miliamp current.  sums up 22 watt DC input so more than 10 watt Rf is there. And i think with it DSB exiter might also work.

here is my
1- receiver strip the 20 meter Direct conversion receiver
2- 20 meter linear 20 mb linear
 3- RF linear CW transmitter 14.315 mhz
have a look please.

Now, first part done next is to put it on air and re-generate the QRM.

Mount Girnar, ARSI VHF HF hilltop contest

I live at the foothill of mount girnar and love the Mount Girnar for many many years. I did climbed and walked round the  girnar, we call it pari-krama. I had many many fond memories girnar . Starting from as a small kid tugged by adults to this mid age. I love the girnar mountain. I enjoyed its presence as resident, as nature lover, envirnmentalist, as rock climber, as ham, as a spiritual person. Sometimes i walk upto it to find myself.

Here are few fotographs found from the fake book of vu3kdg (sk). There are two hams with bag the ever energetic vu3hmm, ghanubha, and another friend nanu holding the beam antenna.

Why i was not there ? they did not find me at my QTH so went alone. event is of 2018. I hope to go one day and do the SOTA.