Thursday, March 3, 2011

New Amp 006, Finished at last.

Hello and welcome to the final part of the "new amp" project ?.
Sorry for in the delay in posting the final part of the new amp.
Since the last update to the Blog, the transceiver has been up and running for a couple of weeks.
As I mensioned in a previous Blog Post, I had left the rig running for up to half an hour at times and in some cases a full hour,the unit would never be transmitting for such a long period in real life, but it is good to know that your project is up for the job.
These trials would show up any faults weither in the design or soldering,and at home on the test bench not on a hill miles away. The RF power was put into a dummy load with the fans running on the rig,the heatsink was warm at most after the hour. It was hot hot hot after 20 minutes with no fans running but still less than the manufactures maximum recomended temperature,thanks to the large heat simk.
Strange as it may sound, I also brought it with me in the car even when it was not compleat just to see how it held together and if any parts would vibrate,as I would be using it /m as well as /p when it was finished. I needed to know the build quality and that the  project would not shake apart.




In photo1on the left,you can see a small audio amplifier,this was needed as the output from the monitor was very low and no sound could be heard from the speaker I installed in the front of the unit.There was plenty of audio when I used some headphones, but this would not be ideal if Iwas
                              giving a demo with the unit.


23cms preamps
 

In photo2 on the left, you can see a couple of  Preamps (35db on left an 30db on right) one of these will help with the rx when I install it later.
As you can see there is a differents in the size of the preamps, and indeed the same can be said about the coaxal relays that can be seen in photo 3 below,and in photo 4 below that.

N type relays

















SMA relays















When it is been installed I will also be replacing the relay for a 4/5 pole type.With this relay I will be able to bypass the preamp and use it when required.As I said this will be done when the unit has a few hours of work done as /p and at QTHR.
In the photos you can see the new parts to be installed. I dont know what to do when it comes to trying to hide the connecting dc cables and coaxal cables.Who knows what amp mk2 will be like,maybe I will install a sub chasis made of a non conductive material, pcb board,or a plastic chopping board would be a good choice, and they are available in various sizes.
Below you can see some other pictures,the images on the monitors are.The top one shows an image of
EI 4 DIB/P on HF at the Skerries Mills on the Air in 2010.
Bottom image is part of the /P station of Derek EI 7 CHB also at the Mills on the Air weekend.
73' from Pat EI 2 HX.