Uploaded November 2023 | Updated September 2026, 1 week ago
Only $5 for 10 PCBs and every new member get $5 bonus. + Express 24 hour / 48 hour service on pcbway.com
In the late 50's and early 60's, many tube radio manufacturers experimented with new ways to project sound from their devices. All in an attempt to stand out from their competition, and create more pleasing and rich audio experiences. Some systems got it right, and some ... well, let's just say they made notable efforts.
This Graetz Melodia model offered an innovation which they called 'Raumklang' and which used a 'Schallkompressor' - a sound compressor - to project the sound around an entire room. It looks like a weird piping system that you'd expect to feel hot air being jetted out from spaced holes along its length, but at this stage I cannot really attest to its efficacy (or otherwise) as it's not yet been restored and tested by myself.
I must admit that this feature was one of the reasons that I decided to acquire and restore this model, because curiosity is a fundamental element of my reason for loving this hobby.
If you're also curious, stick around for this project and find out for yourself.
You can now support the channel:
patreon.com/mcaldeira
paypal.me/macaldeira
Other channels mentioned in this video:
@DavidTipton101
#tuberadios #antiqueradio #radiorestoration
______HUNDREDS OF OTHER VIDEOS TO CHOOSE FROM_____
DIY TEST GEAR: The title says it all:
youtube.com/watch?v=7buNHf6HoDw&list=PLy5M_tA9ux7KkjmWX0I0zNocg6NF33EfL
RESTORATION BUILDING BLOCKS: A series of videos showing detailed steps used the restoration process of tube equipment:
youtube.com/watch?v=7xvTGd4ysRE&list=PLy5M_tA9ux7JSYx8z2mw303vx287LHpzf
HowTo's: Various videos on some simple techniques and projects:
youtube.com/watch?v=lgr-J_D6pSU&list=PLy5M_tA9ux7K3B77iUGyLPai3RIvJOrkO
See also playlists on some other completed restoration projects.
PHILIPS BX750A:
youtube.com/watch?v=i8U9Lteja5o&list=PLy5M_tA9ux7IG6XgctidGO0u0DeT3_CxF
TELEFUNKEN OPUS 2114:
youtube.com/watch?v=_HO2bjY5vuw&list=PLy5M_tA9ux7LhcZ9h9plfTFmjaM1mcifu
SABA UW-175-Z 3D:
youtube.com/watch?v=cca4i60ZLw4&list=PLy5M_tA9ux7IWL18nsrSf4RnjsuPjHC-p
GRUNDIG 1070:
youtube.com/watch?v=i4J5l0fwhko&list=PLy5M_tA9ux7JgnyYPRWOK763aJ8bg3iCI
SCHAUB-LORENZ GOLDY 58 type 3020:
youtube.com/watch?v=RSbt7qVed78&list=PLy5M_tA9ux7IBse5G--Kl89SPS9sATXfZ
BUSH VHF64:
youtube.com/watch?v=U--6JymkQ1M&list=PLy5M_tA9ux7KsvN5M48cX6cxN4jSz0s3X
GRUNDIG 3060A:
youtube.com/watch?v=7x2sK2GSYeE&list=PLy5M_tA9ux7L8e9h8lrHGREPqcgWO-YQm
TELEFUNKEN OPERETTE 8:
youtube.com/watch?v=5IsACM0mPzs&list=PLy5M_tA9ux7K3SXDv8Hu4uAyl1O7NE5dc
GRAETZ SUPER 171W:
youtube.com/watch?v=MhG-CH0gqm4&list=PLy5M_tA9ux7IjUykGE8neJSI6GUxMl2YG
LOEWE-OPTA MAGNET 3737W:
youtube.com/watch?v=ZSZBJ5sKQm8&list=PLy5M_tA9ux7J_hzDhnF8rs2c7wmgGfRlK
BRAUN ATELIER 3:
youtube.com/playlist?list=PLy5M_tA9ux7L3k5nPRvrk1aH764QRCTqE
LOEWE-OPTA TRUXA STEREO 4741W:
youtube.com/playlist?list=PLy5M_tA9ux7KhVk0KqPx0Wkh2KO_5f2fQ
GRAETZ COMEDIA 616:
youtube.com/watch?v=fwmW9k3TwNE&list=PLy5M_tA9ux7L5sAApLzV6xoYzmRNJpMW5
SABA FREIBURG W2:
youtube.com/playlist?list=PLy5M_tA9ux7IqvS-LshUGpE1D_WY6mrZe
GRAETZ MUSICA 4R417:
youtube.com/playlist?list=PLy5M_tA9ux7Ios98E59dWjwc2SRJyxwIn
You may also be interested in ...
CAPACITOR LEAKAGE TESTER:
youtube.com/watch?v=0pySErvzUIY&list=PLy5M_tA9ux7KWexvEjLB0SANSxQXi0zTS
Only $5 for 10 PCBs and every new member get $5 bonus. + Express 24 hour / 48 hour service on pcbway.com
In the late 50's and early 60's, many tube radio manufacturers experimented with new ways to project sound from their devices. All in an attempt to stand out from their competition, and create more pleasing and rich audio experiences. Some systems got it right, and some ... well, let's just say they made notable efforts.
This Graetz Melodia model offered an innovation which they called 'Raumklang' and which used a 'Schallkompressor' - a sound compressor - to project the sound around an entire room. It looks like a weird piping system that you'd expect to feel hot air being jetted out from spaced holes along its length, but at this stage I cannot really attest to its efficacy (or otherwise) as it's not yet been restored and tested by myself.
I must admit that this feature was one of the reasons that I decided to acquire and restore this model, because curiosity is a fundamental element of my reason for loving this hobby.
If you're also curious, stick around for this project and find out for yourself.
You can now support the channel:
patreon.com/mcaldeira
paypal.me/macaldeira
Other channels mentioned in this video:
@DavidTipton101
#tuberadios #antiqueradio #radiorestoration
______HUNDREDS OF OTHER VIDEOS TO CHOOSE FROM_____
DIY TEST GEAR: The title says it all:
youtube.com/watch?v=7buNHf6HoDw&list=PLy5M_tA9ux7KkjmWX0I0zNocg6NF33EfL
RESTORATION BUILDING BLOCKS: A series of videos showing detailed steps used the restoration process of tube equipment:
youtube.com/watch?v=7xvTGd4ysRE&list=PLy5M_tA9ux7JSYx8z2mw303vx287LHpzf
HowTo's: Various videos on some simple techniques and projects:
youtube.com/watch?v=lgr-J_D6pSU&list=PLy5M_tA9ux7K3B77iUGyLPai3RIvJOrkO
See also playlists on some other completed restoration projects.
PHILIPS BX750A:
youtube.com/watch?v=i8U9Lteja5o&list=PLy5M_tA9ux7IG6XgctidGO0u0DeT3_CxF
TELEFUNKEN OPUS 2114:
youtube.com/watch?v=_HO2bjY5vuw&list=PLy5M_tA9ux7LhcZ9h9plfTFmjaM1mcifu
SABA UW-175-Z 3D:
youtube.com/watch?v=cca4i60ZLw4&list=PLy5M_tA9ux7IWL18nsrSf4RnjsuPjHC-p
GRUNDIG 1070:
youtube.com/watch?v=i4J5l0fwhko&list=PLy5M_tA9ux7JgnyYPRWOK763aJ8bg3iCI
SCHAUB-LORENZ GOLDY 58 type 3020:
youtube.com/watch?v=RSbt7qVed78&list=PLy5M_tA9ux7IBse5G--Kl89SPS9sATXfZ
BUSH VHF64:
youtube.com/watch?v=U--6JymkQ1M&list=PLy5M_tA9ux7KsvN5M48cX6cxN4jSz0s3X
GRUNDIG 3060A:
youtube.com/watch?v=7x2sK2GSYeE&list=PLy5M_tA9ux7L8e9h8lrHGREPqcgWO-YQm
TELEFUNKEN OPERETTE 8:
youtube.com/watch?v=5IsACM0mPzs&list=PLy5M_tA9ux7K3SXDv8Hu4uAyl1O7NE5dc
GRAETZ SUPER 171W:
youtube.com/watch?v=MhG-CH0gqm4&list=PLy5M_tA9ux7IjUykGE8neJSI6GUxMl2YG
LOEWE-OPTA MAGNET 3737W:
youtube.com/watch?v=ZSZBJ5sKQm8&list=PLy5M_tA9ux7J_hzDhnF8rs2c7wmgGfRlK
BRAUN ATELIER 3:
youtube.com/playlist?list=PLy5M_tA9ux7L3k5nPRvrk1aH764QRCTqE
LOEWE-OPTA TRUXA STEREO 4741W:
youtube.com/playlist?list=PLy5M_tA9ux7KhVk0KqPx0Wkh2KO_5f2fQ
GRAETZ COMEDIA 616:
youtube.com/watch?v=fwmW9k3TwNE&list=PLy5M_tA9ux7L5sAApLzV6xoYzmRNJpMW5
SABA FREIBURG W2:
youtube.com/playlist?list=PLy5M_tA9ux7IqvS-LshUGpE1D_WY6mrZe
GRAETZ MUSICA 4R417:
youtube.com/playlist?list=PLy5M_tA9ux7Ios98E59dWjwc2SRJyxwIn
You may also be interested in ...
CAPACITOR LEAKAGE TESTER:
youtube.com/watch?v=0pySErvzUIY&list=PLy5M_tA9ux7KWexvEjLB0SANSxQXi0zTS









![Build Your Own Under-Shelf Test Modules – Fusion 360 & 3D Files Shared #pcbway#
Only $5 for 10 PCBs and every new member get $5 bonus. + Express 24 hour / 48 hour service on https://www.pcbway.com/ ➠ ➠ ➠Over the years, I’ve designed a set of under-shelf test modules that have become essential to my electronics restoration and repair work. Many of you have asked how you can build your own — so I’ve finally created a standardised module system that you can 3D print and customise yourself.
In this video, I walk through how I created the new modular enclosure, which fits neatly under a typical workbench shelf, and how I’m converting one of my existing modules to this new format. I also share:
🔹 Fusion 360 source file
🔹 3D print STL files
🔹 Artwork design file
🔹 Direct link to order the #D prints from PCBWay
Whether you’re building your own capacitor tester, Dummy Load, or RF Attenuator module — this system is meant to be flexible, functional, and free to use.
▶ Grab the files here: [📂 https://drive.google.com/drive/folders/1fRZpdGQm8uutbLAybnUgg2Tk6hwzeBXG?usp=sharing]
▶ Order PCB directly (optional): [🔗 https://www.pcbway.com/project/shareproject/EO_N_Under_Shelf_Module_for_Electronics_Test_Gear_e9635e47.html]
I don’t sell anything myself — this is just a personal project I’m happy to share with the community. If you end up building one, I’d love to hear about it in the comments!
🙏 Want to support the channel? ●●●●●●
https://www.patreon.com/mcaldeira
https://paypal.me/macaldeira
This video shows how to build a modular under-shelf test system for electronics repair, including a 3D printable enclosure, shared Fusion 360 CAD files, artwork for front panels, and a link to PCBWay to order PCBs. Ideal for electronics hobbyists, radio restorers, or anyone wanting to build their own workbench test modules.
HUNDREDS OF OTHER VIDEOS TO CHOOSE FROM
DIY TEST GEAR: The title says it all:
https://www.youtube.com/watch?v=7buNHf6HoDw&list=PLy5M_tA9ux7KkjmWX0I0zNocg6NF33EfL
RESTORATION BUILDING BLOCKS: A series of videos showing detailed steps used the restoration process of tube equipment:
https://www.youtube.com/watch?v=7xvTGd4ysRE&list=PLy5M_tA9ux7JSYx8z2mw303vx287LHpzf
HowTos: Various videos on some simple techniques and projects:
https://www.youtube.com/watch?v=lgr-J_D6pSU&list=PLy5M_tA9ux7K3B77iUGyLPai3RIvJOrkO
See also playlists on some other completed restoration projects.
PHILIPS BX750A:
https://www.youtube.com/watch?v=i8U9Lteja5o&list=PLy5M_tA9ux7IG6XgctidGO0u0DeT3_CxF
TELEFUNKEN OPUS 2114:
https://www.youtube.com/watch?v HO2bjY5vuw&list=PLy5M_tA9ux7LhcZ9h9plfTFmjaM1mcifu
SABA UW-175-Z 3D:
https://www.youtube.com/watch?v=cca4i60ZLw4&list=PLy5M_tA9ux7IWL18nsrSf4RnjsuPjHC-p
GRUNDIG 1070:
https://www.youtube.com/watch?v=i4J5l0fwhko&list=PLy5M_tA9ux7JgnyYPRWOK763aJ8bg3iCI
SCHAUB-LORENZ GOLDY 58 type 3020:
https://www.youtube.com/watch?v=RSbt7qVed78&list=PLy5M_tA9ux7IBse5G Kl89SPS9sATXfZ
BUSH VHF64:
https://www.youtube.com/watch?v=U 6JymkQ1M&list=PLy5M_tA9ux7KsvN5M48cX6cxN4jSz0s3X
GRUNDIG 3060A:
https://www.youtube.com/watch?v=7x2sK2GSYeE&list=PLy5M_tA9ux7L8e9h8lrHGREPqcgWO-YQm
TELEFUNKEN OPERETTE 8:
https://www.youtube.com/watch?v=5IsACM0mPzs&list=PLy5M_tA9ux7K3SXDv8Hu4uAyl1O7NE5dc
GRAETZ SUPER 171W:
https://www.youtube.com/watch?v=MhG-CH0gqm4&list=PLy5M_tA9ux7IjUykGE8neJSI6GUxMl2YG
BRAUN ATELIER 3:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7L3k5nPRvrk1aH764QRCTqE
LOEWE-OPTA TRUXA STEREO 4741W:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7KhVk0KqPx0Wkh2KO_5f2fQ
SABA FREIBURG W2:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7IqvS-LshUGpE1D_WY6mrZe
You may also be interested in ...
CAPACITOR LEAKAGE TESTER:
https://www.youtube.com/watch?v=0pySErvzUIY&list=PLy5M_tA9ux7KWexvEjLB0SANSxQXi0zTS
#ElectronicsWorkbench #DIYTestGear #3DPrintedElectronics Build Your Own Under-Shelf Test Modules – Fusion 360 & 3D Files Shared #pcbway#](https://i.ytimg.com/vi/Tliq6XaSb9Y/mqdefault.jpg)
