• Stargazing

## Main Question or Discussion Point

Hello PF,
I was wondering if there is any good guide to build a radio telescope that can give me an image not just a graph. I am just a starter so any advice or tips are relly appreciated.

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davenn
Gold Member
2019 Award
an image is build up from lots of graph data sets
go for the graph style for a start, that is going to keep you extremely busy and poor building it

jamalkoiyess
davenn
Gold Member
2019 Award
firstly you need to decide

1) budget
2) what specific object(s) you want to observe ... different ones have different frequencies
3) depending on the answer to #2, that will determine if you will need a dish and low noise amplifiers
or a wire antenna or maybe Yagi antenna(s)

Eg
atmospheric whistlers can be received on 10 - 20 kHz (ELF - VLF)
solar flares from the sun can be received from around 1MHz to 50 MHz (HF to VHF)
Jupiter noise on around 18 - 24 MHz ( HF)

any deep space objects are going to require lots of ground space for BIG antennas and decent money for

Dave

firstly you need to decide

1) budget
2) what specific object(s) you want to observe ... different ones have different frequencies
3) depending on the answer to #2, that will determine if you will need a dish and low noise amplifiers
or a wire antenna or maybe Yagi antenna(s)

Eg
atmospheric whistlers can be received on 10 - 20 kHz (ELF - VLF)
solar flares from the sun can be received from around 1MHz to 50 MHz (HF to VHF)
Jupiter noise on around 18 - 24 MHz ( HF)

any deep space objects are going to require lots of ground space for BIG antennas and decent money for

Dave
I am new to this field so my budget is not more than 200$. I will not take more risk for something i don't know. For the objects i would go for solar flares and the jupiter noise ... sounds more interesting. So any good setup ? davenn Science Advisor Gold Member 2019 Award I am new to this field so my budget is not more than 200$. I will not take more risk for something i don't know.
For the objects i would go for solar flares and the jupiter noise ... sounds more interesting. So any good setup ?
OK $200 is going to be a little difficult but not impossible a "shortwave" HF ( high frequency) receiver that covers say 1MHz to 30MHz .... shop around you may find something second hand for$200 that has respectable receive
an old Yaesu FRG7000, a bit pricier a FRG7700 or a Kenwood R1000

all three of these are 20++ yrs old you wont get anything better unless you are willing to spend lots more
you will still need to get an either an old pen chart recorder and lots of paper or a digitiser ( datalogger) for a computer
eg a picoscope logger https://www.picotech.com/products/data-logger

this is just one brand, there are many others out there, they all come with the driver software for displaying the signal

then you need to get wire etc for making an antenna ... that's almost the cheapest part

you are probably not going to get much change out of $500 - 700 . Dave jamalkoiyess OK$200 is going to be a little difficult but not impossible

a "shortwave" HF ( high frequency) receiver that covers say 1MHz to 30MHz .... shop around
you may find something second hand for $200 that has respectable receive an old Yaesu FRG7000, a bit pricier a FRG7700 or a Kenwood R1000 all three of these are 20++ yrs old you wont get anything better unless you are willing to spend lots more you will still need to get an either an old pen chart recorder and lots of paper or a digitiser ( datalogger) for a computer eg a picoscope logger https://www.picotech.com/products/data-logger this is just one brand, there are many others out there, they all come with the driver software for displaying the signal then you need to get wire etc for making an antenna ... that's almost the cheapest part you are probably not going to get much change out of$500 - 700

.

Dave
But do i need a dish or an antenna ?
I am building it on my own so if you could help me and list the parts that would be a huge thanks for you.

davenn
Gold Member
2019 Award
But do i need a dish or an antenna ?
for the sun, earth atmospherics or Jupiter, just a wire antenna
sun and Jupiter a dipole antenna tuned to around 20 MHz
for earth atmospherics a large multi-turn loop antenna

I am building it on my own so if you could help me and list the parts that would be a huge thanks for you.
you should be seeking out the help of a local amateur (ham) radio operator for some hands on mentoring and guidance

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jamalkoiyess
you should be seeking out the help of a local amateur (ham) radio operator for some hands on mentoring and guidance
Yeah i can get help from a friend in my area who has a masters in electronic physics and works as an electrician so he has the experience.

davenn
davenn
Gold Member
2019 Award
This site suggested a dish however davenn said i should use an antenna ... i am confused [emoji28]
don't be confused
the wire dipole and or yagi antennas are for HF and VHF ..... 1 MHz - 30 MHz ( HF), (30 - 300MHz VHF)

dish antennas are for low band to high band microwave frequencies 1 GHz and up

for you at this time for the least money outlay you need to do as I suggested back in posts # 5 and #7

THEN ONCE you have mastered some of the basics, and started recording signals and still have the interest, then you can start looking at reception in the microwave bands

basically .... learn to crawl before you learn to walk or run
As you move higher and higher in frequency, things get more difficult and more care needs to be taken in construction etc

Dave

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jamalkoiyess
Just for fun, check out this website:

Lots of radio related surplus and unusual parts.... Lots of once very costly and amazingly overengeneered military surplus radio and antenna gear. Never know what you are going to find, and HF range stuff is often in abundance. No affiliation, just occasional customer. YMMV.

Funky retail shop in Lima, OH as well. A fun visit if in the neighborhood.

diogenesNY

jamalkoiyess
sophiecentaur