The Cosmo C1 SDI/HDMI Wireless Video Transmission System from Hollyland allows you to wirelessly transmit high-resolution video up to 1080p60 over long distances up to 1000' to a single receiver, allowing flexible video monitoring and distribution for your studio or field production. This kit consists of a transmitter and a receiver that communicate over the 5.1 to 5.9 GHz wireless frequency range.
The Cosmo C1 SDI/HDMI Wireless Video Transmission System from Hollyland allows you to wirelessly transmit high-resolution video up to 1080p60 over long distances up to 1000' to a single receiver, allowing flexible video monitoring and distribution for your studio or field production. This kit consists of a transmitter and a receiver that communicate over the 5.1 to 5.9 GHz wireless frequency range.
Solid, Secure Wireless Transmission
The Cosmo C1 can transmit video up to 1000' line-of-sight with a low 40 ms latency using the HEVC/H.265 codec. The system operates on the 5 GHz frequency band and uses AES-128 encryption to prevent video leakage. It also supports smart channel selection, allowing the system to choose the cleanest channel for transmission as well as HEVO, an adaptive frequency hopping technology, for seamless retransmission without losing a frame.
Live Video Input/Output
The transmitter offers one HDMI input, one SDI input, and one SDI loop-through output, and the receiver offers two SDI outputs and one HDMI output.
The receiver can also be used for live streaming via its USB Type-C output, supporting UVC applications on your Internet-connected computer.
Input/Output Transmission Formats
Versatile Power and Form Factor
Both compact units also feature a bright, easy-to-read OLED display showing status and configuration
Each unit can be powered via an L-series battery plate, DC input, or with an optional USB power supply via the USB Type-C port
Four standard antennas and two mushroom antennas are supplied for the receiver and transmitter
Each unit is easy to mount just about anywhere using its 1/4"-20 threads and included shoe mount adapter
Multiple Mounting Methods
You can mount the transmitter and receiver using the cold shoe on the front panel for horizontal mounting, and you can utilize the 1/4"-20 thread to mount the unit on a tripod or cage.
Auto Fan Mode
The COSMO C1 can adjust the fan speed according to the device's temperature, and it is so quiet it is hardly felt or heard.
Low-Battery Indicator
Both the Cosmo C1 transmitter and receiver have a low-battery indicator above the LCD on the side. Once the indicator shows red, the device will run out of battery in 20 minutes, so you have plenty of time to replace the battery or connect to a power source.
Receiver/Transmitter: 1x L-Series Mount on Fixed Plate
Power Consumption
Transmitter/Receiver: 9 W
Mounting
Tripod/Accessory Mounting
1x Cold Shoe
General
Environmental Resistance
No
Dimensions
Transmitter/Receiver: 4.5 x 2.8 x 1.3" / 115 x 70 x 32 mm (Excluding Battery Plate)
Weight
Transmitter: 7.55 oz / 214.00 g, Excluding Antenna Receiver: 7.41 oz / 210.00 g, Excluding Antenna
Packaging Info
Package Weight
4.39 lb
Box Dimensions (LxWxH)
11.6 x 10.8 x 5.5"
Hollyland Cosmo C1 Reviews
Works great!
By Nestor
Rated 5 out of 5
Date: 2025-07-02
Solid product, works as advertised, I did not test the range yet.
I love that you can live stream directly trough USB.
THESE ARE FROM HOLLYLAND...NOTHING ELSE TO SAY
By George
Rated 5 out of 5
Date: 2024-09-05
We use multiple sets of Hollyland Wireless transmission systems, including their wireless intercom during every broadcast. None of the Hollyland equipment has ever failed to perform for us whether it's outside in the elements or in a high humidity swimming venue they have done their job. The Cosmo 1's 1000' line of site, quick paring and option of SDI or HDMI fill the bill for us. They are slowly replacing our original Mars 300's which I might add are still working perfectly after 8 years of use. You just can't beat Hollyland for wireless transmission.
See any errors on this page?
How many sets can be used simultaneously on a ...
How many sets can be used simultaneously on a switcher?
Asked by: JUN
If you think of the Hollyland Cosmo C1 SDI/HDMI Wireless Video Transmission System as the cable from the camera, you can use as many as you have camera inputs on the switcher.
Answered by: Dennis L
Date published: 2022-06-23
Does this work with the Mars M1 Enhanced Monitor?
Does this work with the Mars M1 Enhanced Monitor?
Asked by: Jason
No, the Hollyland Cosmo C1 SDI/HDMI Wireless Video Transmission System is not compatible with the Hollyland Mars M1 Enhanced Monitor, however it is compatible with Mars Pro series and Mars 4K video transmission systems. You can also use another Mars M1 enhanced.
Hollyland Mars 4K Wireless Video Transmission System
BH #HOMARS4K
Hollyland Mars 400S PRO SDI/HDMI Wireless Video Transmission System
BH #HOMARS400SPR
Hollyland Mars M1 Enhanced 5.5" Wireless Transceiver Monitor
BH #HOHLMARSM1E
Answered by: Chris H
Date published: 2024-03-28
how many sets C1 set can use at the same time ?
how many sets C1 set can use at the same time ?
Asked by: Thu
Four sets of the Hollyland Cosmo C1 SDI/HDMI Wireless Video Transmission System can be used at the same time.
Answered by: John W
Date published: 2025-02-03
I know that Hollyland claim this unit works ...
I know that Hollyland claim this unit works around 40ms latency but will Cosmo improve latency response for focus pulling under a full sdi solution?
Asked by: Patricio
The Hollyland Cosmo C1 will have 40ms latency at its best when using HDMI or SDI.
Answered by: Peterm
Date published: 2022-06-23
Is there a way to change the dropped signal image ...
Is there a way to change the dropped signal image to something besides the Hollyland logo?
Asked by: Mike
No, the symbols on the Hollyland Cosmo C1 SDI/HDMI Wireless Video Transmission System's display are not changeable.
Answered by: Paige K
Date published: 2022-10-26
, how many devices (tablets, iPhone, ipad, etc) ...
, how many devices (tablets, iPhone, ipad, etc) can be sed for monitoring the live feed ? thanks
Asked by: M
One. The Cosmo C1 can only support 1 Transmitter to 1 Receiver, doesn't support connect via APP
Answered by: hectorm
Date published: 2022-08-05
Will the COSMO C1 cross convert the HDMI in on ...
Will the COSMO C1 cross convert the HDMI in on the transmitter to the SDI out on the receiver? Looking to feed my HDMI on my Z9 to a SDI monitor.
Asked by: Jay
Yes, You will be able to cross convert like that on the Hollyland Cosmo C1 TX/RX.
Answered by: Peterm
Date published: 2022-04-04
so each camera during live streaming has to have ...
so each camera during live streaming has to have one Cosmo C1 each? Normally live stream has multiple cams.
Asked by: Ransom
The Hollyland Cosmo C1 is a 1 to 1 system. Each camera must transmit to a receiver on the other end.
