Looking for what device this is. They’ve put a sticker over it but also been rubbed off once you remove it. They seem to use the same amp but change the chip for 120w - 200w and 300w
https://a.aliexpress.com/_mMaScr4
What device is this amp using ?
-
reverend
- tower block dreamin
- Posts: 282
- Joined: Sat Jul 25, 2020 12:03 pm
Re: What device is this amp using ?
They use various devices, mostly taken out of old cellular amplifiers. The MRF9180 is one example.
if it ain't broke, keep tweaking
-
BriansBrain
- proppa neck!
- Posts: 520
- Joined: Sat Jun 08, 2019 1:22 pm
- Location: Gran Canaria, Spain. One of the 7 islands off the N.W. coast of Africa.
- Contact:
Re: What device is this amp using ?
Mmmmmmmmmm interestingXXL wrote: ↑Thu Dec 29, 2022 5:12 pm Looking for what device this is. They’ve put a sticker over it but also been rubbed off once you remove it. They seem to use the same amp but change the chip for 120w - 200w and 300w
https://a.aliexpress.com/_mMaScr4
High gainOperating power supply: 26-27V
Input power: 0.6-1W
The Most Unique English Speaking Radio Station in the Canaries... Possibly the World.-
XXL
- proppa neck!
- Posts: 537
- Joined: Mon Sep 02, 2019 11:06 am
Re: What device is this amp using ?
Is that good or bad ?
-
BriansBrain
- proppa neck!
- Posts: 520
- Joined: Sat Jun 08, 2019 1:22 pm
- Location: Gran Canaria, Spain. One of the 7 islands off the N.W. coast of Africa.
- Contact:
Re: What device is this amp using ?
The Most Unique English Speaking Radio Station in the Canaries... Possibly the World.-
BriansBrain
- proppa neck!
- Posts: 520
- Joined: Sat Jun 08, 2019 1:22 pm
- Location: Gran Canaria, Spain. One of the 7 islands off the N.W. coast of Africa.
- Contact:
Re: What device is this amp using ?
Here's another even cheaper About €149.73
But without the LPF on ebay
300W 75MHz-120MHz RF Power Amplifier Board Input 27V Working Current 17-18A for FM Transmitter Radio
Specifications:
- Power supply: 27V
- Working current: 17-18A
- Power: 300W (maximum 350W 300W is recommended)
- Frequency range: 75-120MHz
- Input power: 1W
- Output impedance: 50 ohms
- Board size: 10 x 5.4cm/3.9 x 2.1"
But without the LPF on ebay
300W 75MHz-120MHz RF Power Amplifier Board Input 27V Working Current 17-18A for FM Transmitter Radio
Specifications:
- Power supply: 27V
- Working current: 17-18A
- Power: 300W (maximum 350W 300W is recommended)
- Frequency range: 75-120MHz
- Input power: 1W
- Output impedance: 50 ohms
- Board size: 10 x 5.4cm/3.9 x 2.1"
You do not have the required permissions to view the files attached to this post.
The Most Unique English Speaking Radio Station in the Canaries... Possibly the World.-
BriansBrain
- proppa neck!
- Posts: 520
- Joined: Sat Jun 08, 2019 1:22 pm
- Location: Gran Canaria, Spain. One of the 7 islands off the N.W. coast of Africa.
- Contact:
Re: What device is this amp using ?
OK I'm guessing it's a SRF261
It doesn't have the normal mounting flange with the holes for mounting
So they have soldered one on
It doesn't have the normal mounting flange with the holes for mounting
So they have soldered one on
You do not have the required permissions to view the files attached to this post.
The Most Unique English Speaking Radio Station in the Canaries... Possibly the World.-
BriansBrain
- proppa neck!
- Posts: 520
- Joined: Sat Jun 08, 2019 1:22 pm
- Location: Gran Canaria, Spain. One of the 7 islands off the N.W. coast of Africa.
- Contact:
Re: What device is this amp using ?
The Most Unique English Speaking Radio Station in the Canaries... Possibly the World.-
Onlinejvok
- tower block dreamin
- Posts: 301
- Joined: Sun Aug 16, 2020 2:44 pm
Re: What device is this amp using ?
Reckon that heatsinks big enough?
-
XXL
- proppa neck!
- Posts: 537
- Joined: Mon Sep 02, 2019 11:06 am
Re: What device is this amp using ?
Won’t that solder just melt with the heat ? Also what would the 200w device be ? I don’t think it would be an mrf9180.
-
Albert H
- proppa neck!
- Posts: 2957
- Joined: Tue Apr 05, 2016 1:23 am
Re: What device is this amp using ?
The output short circuit test in that video is scary!
The harmonic outputs from that PA are rather nasty - the second is around 48 - 54 dB below the carrier, and the third is generally a bit worse. It would need a good lowpass filter after it to make sure it wouldn't cause interference. You'll notice that they've set the spectrum analyser to show only up to the third - it's probably producing more harmonics above that. The lowpass filter capacitors will be expensive, since they'll have a pretty big voltage across them.
The harmonic outputs from that PA are rather nasty - the second is around 48 - 54 dB below the carrier, and the third is generally a bit worse. It would need a good lowpass filter after it to make sure it wouldn't cause interference. You'll notice that they've set the spectrum analyser to show only up to the third - it's probably producing more harmonics above that. The lowpass filter capacitors will be expensive, since they'll have a pretty big voltage across them.
"Why is my rig humming?"
"Because it doesn't know the words!"
"Because it doesn't know the words!"