{"id":469,"date":"2015-08-02T13:37:55","date_gmt":"2015-08-02T11:37:55","guid":{"rendered":"http:\/\/pa0rwe.nl\/?page_id=469"},"modified":"2015-10-05T16:05:40","modified_gmt":"2015-10-05T14:05:40","slug":"hf-all-band-45w-linear","status":"publish","type":"page","link":"https:\/\/pa0rwe.nl\/?page_id=469","title":{"rendered":"HF All Band 45W Linear"},"content":{"rendered":"

\"Front<\/a><\/p>\n

Toroid King<\/a><\/i><\/span>
\nConrad Electronics<\/a><\/i><\/span><\/p>\n

\n

From a friend (Ben, PB2BN), I have got some PCB’s designed for a HF all band linear. He won’t use them in a short time and he knew that I was searching for a simple all band linear design. The design came from the ARRL handbook and using low-cost power MosFETS (IRF510) and it was also including six low-pass filters.<\/p>\n

After I purchased the desired T-50-x toroids and the BN-43-3312 balun core from the ‘Toroid king’ (very cheap and fast delivery!) and the IRF510 from Conrad Electronics, I start building.
\nBecause of the use of PCB’s, building the linear and the low-pass filters was not very hard to do. After some evenings soldering and core-winding, it was ready for testing. One disadvantage of using these FET’s was the need of a 28 volts power-supply. But lucky me, years ago I have got from my father an aircraft Nickel-Cadmium battery supplying 23 Volts, and free of humming…
\nThe first test was not successful, very unsymmetrical output. No wonder, I put a de-coupler capacitor on the FET output in stead of a power line. After correcting that, the amplifier works fine. I was using a 7 dB attenuator to reduce the 5 Watt output of my transceiver to the 1 Watt input for the amplifier to get about 40-45 Watt of output.<\/p>\n

In the meantime I construct an ‘In-line Monitor’, designed by Cor PA0CHN, to measure the output power of the amplifier. The in-line monitor is a very simple but very useful device to measure high power outputs. It consists of a piece of coax mounted between to connectors (coax shield is mounted only on one end!). The coax is put through a FT…-43 core and on the core are 21 windings, one end to the metal box and the other to the monitor connector, closed with 50 \u03a9<\/span> (2 x 100 \u03a9<\/span>). The attenuation of the monitor output is 30 dB.<\/p>\n

Below you see some pictures of the amplifier PCB’s and when the amplifier is ready for use.<\/p>\n

\"Amplifier<\/a>

Amplifier and Low Pass Filters<\/p><\/div>\n

\"Back<\/a>

Back view of the Amplifier<\/p><\/div><\/blockquote>\n

\n

On the ‘Dag van de Radio Amateur’ in 2011, I found a very nice 24V 2.5A power supply (switched). This power supply was originally used in medical equipment, so it doesn’t produce any HF noise and it is sealed in a heavy aluminum case. Also the DC lines are very clean.
\nThe power supply has Brand \/ Type: SCIE AMS 24 2500 GD.<\/p>\n

\"Powersupply\"<\/a>

Powersupply<\/p><\/div><\/blockquote>\n","protected":false},"excerpt":{"rendered":"

Toroid King Conrad Electronics From a friend (Ben, PB2BN), I have got some PCB’s designed for a HF all band linear. He won’t use them in a short time and he knew that I was searching for a simple all band linear design. The design came from the ARRL handbook and using low-cost power MosFETS […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":["post-469","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=\/wp\/v2\/pages\/469","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=469"}],"version-history":[{"count":5,"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=\/wp\/v2\/pages\/469\/revisions"}],"predecessor-version":[{"id":705,"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=\/wp\/v2\/pages\/469\/revisions\/705"}],"wp:attachment":[{"href":"https:\/\/pa0rwe.nl\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=469"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}