Unterschiede

Hier werden die Unterschiede zwischen zwei Versionen angezeigt.

--- projekte:3cmcompacttrv:start [2022/03/20 16:28] – [RX IF Filter] yc
+++ projekte:3cmcompacttrv:start [2022/03/20 17:02] – [Compact 10 GHz transverter] yc
@@ Zeile 4: / Zeile 4: @@
 {{:projekte:3cmcompacttrv:cambridge_pcb.jpg?600|}}
-First all the details of the modules were reverse engineered(documented [[projekte:3cmcompacttrv:reversing|here]] in german) and a concept for the usage as a 3cm transverter was worked out. A first prototype was tinkered together and performed very well:
+schematics: {{ :projekte:3cmcompacttrv:10g_cambridge.pdf |}}\\
+project files: [[https://git.loetlabor-jena.de/yc/10g_cambridge|10g_cambridge]]
-{{:projekte:3cmcompacttrv:prototype.jpg?400|}}
+First all the details of the modules were reverse engineered(documented [[projekte:3cmcompacttrv:reversing|here]] in german) and a concept for the usage as a 3cm transverter was worked out.
 ===== Concept =====
 The idea is to use as much as possible parts from the original design and adapt them to a simplex transverter with the same IF for receiving and transmitting.
@@ Zeile 25: / Zeile 25: @@
 The original ceramic filter is removed and the attenuators are replaced by 0R resistors.
 {{:projekte:3cmcompacttrv:tx_if_filter.jpg?400|}}
+In theory image rejection by the quadrature mixer can be tuned to -60 dBc or better but thermal drift limits the image rejection to about -50 dBc. A pipecap filter with a 28 mm pipecap is added between the transverter board and the rf board.
+{{:projekte:3cmcompacttrv:cambridge_if2.jpg?400|}}
+project files: [[https://git.loetlabor-jena.de/yc/10g_cambridge|if2_cambridge]]\\
+errata:
+  * MMCX instead of MCX used, fix in next revision
 ==== PA Power Supply ====
 The 48V DC/DC module and TR4 are removed. A IRLML6402 is placed upside down on the TR4 footprint as shown in the picture. With two additional wires the drain voltage is switched on when the negative gate voltage is there.
 {{:projekte:3cmcompacttrv:pa_ps.jpg?400|}}
 ==== RX IF Filter ====
-The original 70 MHz IF filter is not used and the signal path is switched to the second not populated filter footprint. A pcb with a 3rd order 50 MHz bandpass filter was made which fits on this footprint.
+The original 70 MHz IF filter is not used and the signal path is switched to the second not populated filter footprint. A pcb with a 3rd order 50 MHz bandpass filter was made and fits on this footprint.
 {{:projekte:3cmcompacttrv:rx_if_filter.jpg?400|}}
+schematics: {{ :projekte:3cmcompacttrv:rx_if_filter_scm.pdf | RX IF filter}}\\
+project files: [[https://git.loetlabor-jena.de/yc/10g_cambridge|if_cambridge]]