Presentamos un circuito de un excelente amplificador comercial de alta fidelidad del tiempo de las válvulas (década de 50 y 60) utilizando válvulas pentodo de potencia EL84 o 6BQ5.

El amplificador tiene la salida en push-pull y los elementos críticos, como en todos los proyectos valvulados son los transformadores que, si no se obtienen de equipos antiguos, deben ser enrollados en casas especializadas.

El transformador de alimentación tiene un secundario de 185 +185 V con 220 mA y otro de 6,3 V + 12 V para los filamentos de las válvulas. El primario puede también ser de 110 V. El transformador de salida es del tipo ultra-lineal para la válvula EL84.

Los capacitores electrolíticos del filtro de fuente deben tener tensiones de trabajo de 450 V. El circuito tiene salidas de 4, 8 y 16 ohms.

Este tipo de amplificador se encuentra en amplificadores tradicionales como los de Geloso, muy famosos en la época por su calidad de sonido. El amplificador mostrado es monofónico y se deben montar dos unidades para una versión estéreo. La fuente puede ser única, con un transformador de 500 mA, en este caso.

Observamos la necesidad de un buen diseño de chasis y conexiones blindadas para las señales para que no ocurra la captación de zumbidos.

 

En la figura 1 tenemos el diagrama completo del amplificador.

 

Amplificador con la EL84 u 6BQ5
Amplificador con la EL84 u 6BQ5 | Haga click en la imagen para ampliar |

 

 

Lista de materiales

V1 - 12AX7 - válvula

V2, V3 - EL84 / 6BQ5 - Válvulas

C1, C2 - 47 nF - 600 V - capacitores cerámicos

C3 - 250 uF x 6 V - capacitor electrolítico

C4, C5 - 40 uF x 150 V - capacitores electrolíticos

C6 - 100 pF x 600 V - capacitor de cerámica

C7a / b / c - 60/40/20 uF x 450 V - capacitor electrolítico triple o tres capacitores independientes con los valores indicados o próximos

C8 - 100 uF x 300 V - capacitor electrolítico

D1, D2 - 600 V x 1 A - diodos - 1N4007

J1 - Jaque de entrada (RCA)

L1 - 2 H x 200 mA - choque de filtro

R3, R4 -10 ohms x ½ W - resistores

R1, R2, R7, R8, R9, R10 - 1 M ohm - 1/8 W

R5 - 2k2 x ½ W - resistor

R6 - 330 ohms x ½ W - resistor

R11, R12 - 1k5 x ½ W - resistores

R13 - 5k6 x ½ W - resistor

R14 - 220k x ½ W - resistor

R15 - 6,8 ohms x 1 W - resistorR16 - 22 ohms x 2 W - resistorT1, T2 - Transformadores - Ver texto

Varios:

Chasis, cable de fuerza, sockets para válvulas, hilos, soldadura, etc.

 

 

18.924MBMemory Usage46.39msRequest Duration
Joomla! Version5.2.3
PHP Version8.3.20
Identityguest
Response200
Templatecassiopeia
Database
Server
mysql
Version
10.5.22-MariaDB
Collation
latin1_swedish_ci
Conn Collation
utf8mb4_general_ci
$_GET
[]
$_POST
[]
$_SESSION
array:1 [ "joomla" => "***redacted***" ]
$_COOKIE
[]
$_SERVER
array:49 [ "USER" => "apache" "HOME" => "/usr/share/httpd" "PATH_TRANSLATED" => "redirect:/ind...
session
array:3 [ "counter" => 1 "timer" => array:3 [ "start" => 1752304365 "last" => 1752304365...
registry
array:3 [ "data" => [] "initialized" => false "separator" => "." ]
user
array:21 [ "id" => 0 "name" => null "username" => null "email" => null "password" => "***r...
  • afterLoad (85.41KB) (226μs)
  • afterInitialise (1.14MB) (3.9ms)
  • afterRoute (179.16KB) (1.29ms)
  • beforeRenderComponent com_content (100.69KB) (449μs)
  • Before Access::preloadComponents (all components) (33.45KB) (316μs)
  • After Access::preloadComponents (all components) (107.06KB) (769μs)
  • Before Access::preloadPermissions (com_content) (1.57KB) (8μs)
  • After Access::preloadPermissions (com_content) (16.22MB) (21.44ms)
  • Before Access::getAssetRules (id:25832 name:com_content.article.29498) (514.65KB) (1.48ms)
  • After Access::getAssetRules (id:25832 name:com_content.article.29498) (7.38KB) (134μs)
  • afterRenderComponent com_content (364.84KB) (8.05ms)
  • afterDispatch (2.25KB) (50μs)
  • beforeRenderRawModule mod_articles_category (Banco de Circuitos) (358.53KB) (1.87ms)
  • afterRenderRawModule mod_articles_category (Banco de Circuitos) (15.43KB) (388μs)
  • beforeRenderRawModule mod_finder (Busca_inteligente) (5.9KB) (101μs)
  • afterRenderRawModule mod_finder (Busca_inteligente) (129.21KB) (1.34ms)
  • beforeRenderModule mod_articles_category (Banco de Circuitos) (9.27KB) (619μs)
  • afterRenderModule mod_articles_category (Banco de Circuitos) (5.47KB) (75μs)
  • beforeRenderModule mod_finder (Busca_inteligente) (6.64KB) (220μs)
  • afterRenderModule mod_finder (Busca_inteligente) (4.44KB) (47μs)
  • afterRender (250.06KB) (3.48ms)
  • 1 x After Access::preloadPermissions (com_content) (16.22MB) (46.21%)
    21.44ms
    1 x afterRenderComponent com_content (364.84KB) (17.36%)
    8.05ms
    1 x afterInitialise (1.14MB) (8.42%)
    3.90ms
    1 x afterRender (250.06KB) (7.5%)
    3.48ms
    1 x beforeRenderRawModule mod_articles_category (Banco de Circuitos) (358.53KB) (4.03%)
    1.87ms
    1 x Before Access::getAssetRules (id:25832 name:com_content.article.29498) (514.65KB) (3.18%)
    1.48ms
    1 x afterRenderRawModule mod_finder (Busca_inteligente) (129.21KB) (2.88%)
    1.34ms
    1 x afterRoute (179.16KB) (2.78%)
    1.29ms
    1 x After Access::preloadComponents (all components) (107.06KB) (1.66%)
    769μs
    1 x beforeRenderModule mod_articles_category (Banco de Circuitos) (9.27KB) (1.33%)
    619μs
    1 x beforeRenderComponent com_content (100.69KB) (0.97%)
    449μs
    1 x afterRenderRawModule mod_articles_category (Banco de Circuitos) (15.43KB) (0.84%)
    388μs
    1 x Before Access::preloadComponents (all components) (33.45KB) (0.68%)
    316μs
    1 x afterLoad (85.41KB) (0.49%)
    226μs
    1 x beforeRenderModule mod_finder (Busca_inteligente) (6.64KB) (0.47%)
    220μs
    1 x After Access::getAssetRules (id:25832 name:com_content.article.29498) (7.38KB) (0.29%)
    134μs
    1 x beforeRenderRawModule mod_finder (Busca_inteligente) (5.9KB) (0.22%)
    101μs
    1 x afterRenderModule mod_articles_category (Banco de Circuitos) (5.47KB) (0.16%)
    75μs
    1 x afterDispatch (2.25KB) (0.11%)
    50μs
    1 x afterRenderModule mod_finder (Busca_inteligente) (4.44KB) (0.1%)
    47μs
    1 x Before Access::preloadPermissions (com_content) (1.57KB) (0.02%)
    8μs
21 statements were executed, 5 of which were duplicates, 16 unique12.01ms1.55MB
  • SELECT @@SESSION.sql_mode;28μs968B/libraries/src/Session/MetadataManager.php:184Copy
  • SELECT `session_id` FROM `incbmx_session` WHERE `session_id` = :session_id LIMIT 166μs1.3KBParams/libraries/src/Session/MetadataManager.php:187Copy
  • INSERT INTO `incbmx_session` (`session_id`,`guest`,`time`,`userid`,`username`,`client_id`) VALUES (:session_id, :guest, :time, :user_id, :username, :client_id)129μs944BParams/libraries/src/Session/MetadataManager.php:260Copy
  • SELECT `id`,`rules` FROM `incbmx_viewlevels`43μs656B/libraries/src/Access/Access.php:955Copy
  • SELECT `b`.`id` FROM `incbmx_usergroups` AS `a` LEFT JOIN `incbmx_usergroups` AS `b` ON `b`.`lft` <= `a`.`lft` AND `b`.`rgt` >= `a`.`rgt` WHERE `a`.`id` = :guest63μs1.64KBParams/libraries/src/Access/Access.php:868Copy
  • SELECT `c`.`id`,`c`.`asset_id`,`c`.`access`,`c`.`alias`,`c`.`checked_out`,`c`.`checked_out_time`,`c`.`created_time`,`c`.`created_user_id`,`c`.`description`,`c`.`extension`,`c`.`hits`,`c`.`language`,`c`.`level`,`c`.`lft`,`c`.`metadata`,`c`.`metadesc`,`c`.`metakey`,`c`.`modified_time`,`c`.`note`,`c`.`params`,`c`.`parent_id`,`c`.`path`,`c`.`published`,`c`.`rgt`,`c`.`title`,`c`.`modified_user_id`,`c`.`version`, CASE WHEN CHAR_LENGTH(`c`.`alias`) != 0 THEN CONCAT_WS(':', `c`.`id`, `c`.`alias`) ELSE `c`.`id` END as `slug` FROM `incbmx_categories` AS `s` INNER JOIN `incbmx_categories` AS `c` ON (`s`.`lft` <= `c`.`lft` AND `c`.`lft` < `s`.`rgt`) OR (`c`.`lft` < `s`.`lft` AND `s`.`rgt` < `c`.`rgt`) WHERE (`c`.`extension` = :extension OR `c`.`extension` = 'system') AND `c`.`published` = 1 AND `s`.`id` = :id ORDER BY `c`.`lft`281μs20.2KBParams/libraries/src/Categories/Categories.php:375Copy
  • SELECT `id`,`name`,`rules`,`parent_id` FROM `incbmx_assets` WHERE `name` IN (:preparedArray1,:preparedArray2,:preparedArray3,:preparedArray4,:preparedArray5,:preparedArray6,:preparedArray7,:preparedArray8,:preparedArray9,:preparedArray10,:preparedArray11,:preparedArray12,:preparedArray13,:preparedArray14,:preparedArray15,:preparedArray16,:preparedArray17,:preparedArray18,:preparedArray19,:preparedArray20,:preparedArray21,:preparedArray22,:preparedArray23,:preparedArray24,:preparedArray25,:preparedArray26,:preparedArray27,:preparedArray28,:preparedArray29,:preparedArray30,:preparedArray31,:preparedArray32,:preparedArray33,:preparedArray34,:preparedArray35,:preparedArray36,:preparedArray37,:preparedArray38,:preparedArray39)603μs7.44KBParams/libraries/src/Access/Access.php:357Copy
  • SELECT `id`,`name`,`rules`,`parent_id` FROM `incbmx_assets` WHERE `name` LIKE :asset OR `name` = :extension OR `parent_id` = 08.02ms1.48MBParams/libraries/src/Access/Access.php:301Copy
  • SHOW FULL COLUMNS FROM `incbmx_content`450μs2.39KB/libraries/vendor/joomla/database/src/Mysqli/MysqliDriver.php:587Copy
  • UPDATE `incbmx_content` SET `hits` = (`hits` + 1) WHERE `id` = '29498'237μs48B/libraries/src/Table/Table.php:1348Copy
  • SELECT `a`.`id`,`a`.`asset_id`,`a`.`title`,`a`.`alias`,`a`.`introtext`,`a`.`fulltext`,`a`.`state`,`a`.`catid`,`a`.`created`,`a`.`created_by`,`a`.`created_by_alias`,`a`.`modified`,`a`.`modified_by`,`a`.`checked_out`,`a`.`checked_out_time`,`a`.`publish_up`,`a`.`publish_down`,`a`.`images`,`a`.`urls`,`a`.`attribs`,`a`.`version`,`a`.`ordering`,`a`.`metakey`,`a`.`metadesc`,`a`.`access`,`a`.`hits`,`a`.`metadata`,`a`.`featured`,`a`.`language`,`fp`.`featured_up`,`fp`.`featured_down`,`c`.`title` AS `category_title`,`c`.`alias` AS `category_alias`,`c`.`access` AS `category_access`,`c`.`language` AS `category_language`,`fp`.`ordering`,`u`.`name` AS `author`,`parent`.`title` AS `parent_title`,`parent`.`id` AS `parent_id`,`parent`.`path` AS `parent_route`,`parent`.`alias` AS `parent_alias`,`parent`.`language` AS `parent_language`,ROUND(`v`.`rating_sum` / `v`.`rating_count`, 1) AS `rating`,`v`.`rating_count` AS `rating_count` FROM `incbmx_content` AS `a` INNER JOIN `incbmx_categories` AS `c` ON `c`.`id` = `a`.`catid` LEFT JOIN `incbmx_content_frontpage` AS `fp` ON `fp`.`content_id` = `a`.`id` LEFT JOIN `incbmx_users` AS `u` ON `u`.`id` = `a`.`created_by` LEFT JOIN `incbmx_categories` AS `parent` ON `parent`.`id` = `c`.`parent_id` LEFT JOIN `incbmx_content_rating` AS `v` ON `a`.`id` = `v`.`content_id` WHERE ( (`a`.`id` = :pk AND `c`.`published` > 0) AND (`a`.`publish_up` IS NULL OR `a`.`publish_up` <= :publishUp)) AND (`a`.`publish_down` IS NULL OR `a`.`publish_down` >= :publishDown) AND `a`.`state` IN (:preparedArray1,:preparedArray2)204μs6.12KBParams/components/com_content/src/Model/ArticleModel.php:215Copy
  • SELECT `c`.`id`,`c`.`asset_id`,`c`.`access`,`c`.`alias`,`c`.`checked_out`,`c`.`checked_out_time`,`c`.`created_time`,`c`.`created_user_id`,`c`.`description`,`c`.`extension`,`c`.`hits`,`c`.`language`,`c`.`level`,`c`.`lft`,`c`.`metadata`,`c`.`metadesc`,`c`.`metakey`,`c`.`modified_time`,`c`.`note`,`c`.`params`,`c`.`parent_id`,`c`.`path`,`c`.`published`,`c`.`rgt`,`c`.`title`,`c`.`modified_user_id`,`c`.`version`, CASE WHEN CHAR_LENGTH(`c`.`alias`) != 0 THEN CONCAT_WS(':', `c`.`id`, `c`.`alias`) ELSE `c`.`id` END as `slug` FROM `incbmx_categories` AS `s` INNER JOIN `incbmx_categories` AS `c` ON (`s`.`lft` <= `c`.`lft` AND `c`.`lft` < `s`.`rgt`) OR (`c`.`lft` < `s`.`lft` AND `s`.`rgt` < `c`.`rgt`) WHERE (`c`.`extension` = :extension OR `c`.`extension` = 'system') AND `c`.`access` IN (:preparedArray1,:preparedArray2) AND `c`.`published` = 1 AND `s`.`id` = :id ORDER BY `c`.`lft`200μs3.92KBParams/libraries/src/Categories/Categories.php:375Copy
  • SELECT `m`.`tag_id`,`t`.* FROM `incbmx_contentitem_tag_map` AS `m` INNER JOIN `incbmx_tags` AS `t` ON `m`.`tag_id` = `t`.`id` WHERE `m`.`type_alias` = :contentType AND `m`.`content_item_id` = :id AND `t`.`published` = 1 AND `t`.`access` IN (:preparedArray1,:preparedArray2)250μs3.97KBParams/libraries/src/Helper/TagsHelper.php:388Copy
  • SELECT `c`.`id`,`c`.`asset_id`,`c`.`access`,`c`.`alias`,`c`.`checked_out`,`c`.`checked_out_time`,`c`.`created_time`,`c`.`created_user_id`,`c`.`description`,`c`.`extension`,`c`.`hits`,`c`.`language`,`c`.`level`,`c`.`lft`,`c`.`metadata`,`c`.`metadesc`,`c`.`metakey`,`c`.`modified_time`,`c`.`note`,`c`.`params`,`c`.`parent_id`,`c`.`path`,`c`.`published`,`c`.`rgt`,`c`.`title`,`c`.`modified_user_id`,`c`.`version`, CASE WHEN CHAR_LENGTH(`c`.`alias`) != 0 THEN CONCAT_WS(':', `c`.`id`, `c`.`alias`) ELSE `c`.`id` END as `slug` FROM `incbmx_categories` AS `s` INNER JOIN `incbmx_categories` AS `c` ON (`s`.`lft` <= `c`.`lft` AND `c`.`lft` < `s`.`rgt`) OR (`c`.`lft` < `s`.`lft` AND `s`.`rgt` < `c`.`rgt`) WHERE (`c`.`extension` = :extension OR `c`.`extension` = 'system') AND `c`.`access` IN (:preparedArray1,:preparedArray2) AND `c`.`published` = 1 AND `s`.`id` = :id ORDER BY `c`.`lft`187μs3.92KBParams/libraries/src/Categories/Categories.php:375Copy
  • SELECT DISTINCT a.id, a.title, a.name, a.checked_out, a.checked_out_time, a.note, a.state, a.access, a.created_time, a.created_user_id, a.ordering, a.language, a.fieldparams, a.params, a.type, a.default_value, a.context, a.group_id, a.label, a.description, a.required, a.only_use_in_subform,l.title AS language_title, l.image AS language_image,uc.name AS editor,ag.title AS access_level,ua.name AS author_name,g.title AS group_title, g.access as group_access, g.state AS group_state, g.note as group_note FROM incbmx_fields AS a LEFT JOIN `incbmx_languages` AS l ON l.lang_code = a.language LEFT JOIN incbmx_users AS uc ON uc.id=a.checked_out LEFT JOIN incbmx_viewlevels AS ag ON ag.id = a.access LEFT JOIN incbmx_users AS ua ON ua.id = a.created_user_id LEFT JOIN incbmx_fields_groups AS g ON g.id = a.group_id LEFT JOIN `incbmx_fields_categories` AS fc ON fc.field_id = a.id WHERE ( (`a`.`context` = :context AND (`fc`.`category_id` IS NULL OR `fc`.`category_id` IN (:preparedArray1,:preparedArray2,:preparedArray3)) AND `a`.`access` IN (:preparedArray4,:preparedArray5)) AND (`a`.`group_id` = 0 OR `g`.`access` IN (:preparedArray6,:preparedArray7)) AND `a`.`state` = :state) AND (`a`.`group_id` = 0 OR `g`.`state` = :gstate) AND `a`.`only_use_in_subform` = :only_use_in_subform ORDER BY a.ordering ASC473μs4.81KBParams/libraries/src/MVC/Model/BaseDatabaseModel.php:164Copy
  • SELECT `c`.`id`,`c`.`asset_id`,`c`.`access`,`c`.`alias`,`c`.`checked_out`,`c`.`checked_out_time`,`c`.`created_time`,`c`.`created_user_id`,`c`.`description`,`c`.`extension`,`c`.`hits`,`c`.`language`,`c`.`level`,`c`.`lft`,`c`.`metadata`,`c`.`metadesc`,`c`.`metakey`,`c`.`modified_time`,`c`.`note`,`c`.`params`,`c`.`parent_id`,`c`.`path`,`c`.`published`,`c`.`rgt`,`c`.`title`,`c`.`modified_user_id`,`c`.`version`, CASE WHEN CHAR_LENGTH(`c`.`alias`) != 0 THEN CONCAT_WS(':', `c`.`id`, `c`.`alias`) ELSE `c`.`id` END as `slug` FROM `incbmx_categories` AS `s` INNER JOIN `incbmx_categories` AS `c` ON (`s`.`lft` <= `c`.`lft` AND `c`.`lft` < `s`.`rgt`) OR (`c`.`lft` < `s`.`lft` AND `s`.`rgt` < `c`.`rgt`) WHERE (`c`.`extension` = :extension OR `c`.`extension` = 'system') AND `c`.`access` IN (:preparedArray1,:preparedArray2) AND `c`.`published` = 1 AND `s`.`id` = :id ORDER BY `c`.`lft`213μs3.92KBParams/libraries/src/Categories/Categories.php:375Copy
  • SELECT `name`,`element` FROM `incbmx_extensions` WHERE `type` = 'plugin' AND `folder` = 'finder' AND `enabled` = 1144μs1.89KB/administrator/components/com_finder/src/Helper/LanguageHelper.php:135Copy
  • SELECT `title` FROM `incbmx_finder_taxonomy` WHERE `parent_id` = 1 AND `state` = 1 AND `access` IN (1,5)98μs648B/administrator/components/com_finder/src/Indexer/Taxonomy.php:325Copy
  • SELECT * FROM `incbmx_schemaorg` WHERE `itemId` = :itemId AND `context` = :context70μs1.55KBParams/plugins/system/schemaorg/src/Extension/Schemaorg.php:403Copy
  • SELECT `a`.`id`,`a`.`asset_id`,`a`.`title`,`a`.`alias`,`a`.`introtext`,`a`.`fulltext`,`a`.`state`,`a`.`catid`,`a`.`created`,`a`.`created_by`,`a`.`created_by_alias`,`a`.`modified`,`a`.`modified_by`,`a`.`checked_out`,`a`.`checked_out_time`,`a`.`publish_up`,`a`.`publish_down`,`a`.`images`,`a`.`urls`,`a`.`attribs`,`a`.`version`,`a`.`ordering`,`a`.`metakey`,`a`.`metadesc`,`a`.`access`,`a`.`hits`,`a`.`metadata`,`a`.`featured`,`a`.`language`,`fp`.`featured_up`,`fp`.`featured_down`,`c`.`title` AS `category_title`,`c`.`alias` AS `category_alias`,`c`.`access` AS `category_access`,`c`.`language` AS `category_language`,`fp`.`ordering`,`u`.`name` AS `author`,`parent`.`title` AS `parent_title`,`parent`.`id` AS `parent_id`,`parent`.`path` AS `parent_route`,`parent`.`alias` AS `parent_alias`,`parent`.`language` AS `parent_language`,ROUND(`v`.`rating_sum` / `v`.`rating_count`, 1) AS `rating`,`v`.`rating_count` AS `rating_count` FROM `incbmx_content` AS `a` INNER JOIN `incbmx_categories` AS `c` ON `c`.`id` = `a`.`catid` LEFT JOIN `incbmx_content_frontpage` AS `fp` ON `fp`.`content_id` = `a`.`id` LEFT JOIN `incbmx_users` AS `u` ON `u`.`id` = `a`.`created_by` LEFT JOIN `incbmx_categories` AS `parent` ON `parent`.`id` = `c`.`parent_id` LEFT JOIN `incbmx_content_rating` AS `v` ON `a`.`id` = `v`.`content_id` WHERE ( (`a`.`id` = :pk AND `c`.`published` > 0) AND (`a`.`publish_up` IS NULL OR `a`.`publish_up` <= :publishUp)) AND (`a`.`publish_down` IS NULL OR `a`.`publish_down` >= :publishDown) AND `a`.`state` IN (:preparedArray1,:preparedArray2)159μs6.17KBParams/components/com_content/src/Model/ArticleModel.php:215Copy
  • SELECT SUM(CASE WHEN `a`.`next_execution` <= :now THEN 1 ELSE 0 END) AS due_count,SUM(CASE WHEN `a`.`locked` IS NULL THEN 0 ELSE 1 END) AS locked_count FROM `incbmx_scheduler_tasks` AS `a` WHERE `a`.`state` = 184μs1.37KBParams/administrator/components/com_scheduler/src/Model/TasksModel.php:465Copy