tag:blogger.com,1999:blog-73286361160058998892026-04-09T20:15:26.442+09:00<i>Something NEW for your eyes !</i>TTT/hirohttp://www.blogger.com/profile/12779801833731212446noreply@blogger.comBlogger432125tag:blogger.com,1999:blog-7328636116005899889.post-26629879981446335302025-12-20T05:30:01.290+09:002026-04-09T20:15:26.394+09:00

【I-Fアンプとマーカー発振器を兼ねる工夫：1AB6/DK96】(まとめ編） Introduction Communication receivers require a calibration function for the readout frequency. I am designing a receiver using vacuum tubes, but I will add the calibration function without increasing the number of tubes. To achieve this, I experimented with a circuit that serves as both a second intermediate frequency amplifier and a marker oscillator. The

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【第２周波数変換をテストする（２）】（追試編） Introduction In the Collins-type receiver I designed in my last blog, the second local oscillator determines the frequency stability. I use a self-converter circuit to save power in my design using battery tubes. I use a 1AB6/DK96 battery tube in the converter circuit, but the local oscillator coil is the most important part.　The first core material I used with high

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【第２周波数変換をテストする】（活用編） Introduction In the Collins-type receiver I designed in my last blog, the second local oscillator determines the frequency stability. I use a self-converter circuit to save power in my design using battery tubes. I use a 1AB6/DK96 battery tube in the converter circuit, but the local oscillator coil is the most important part.　The first core material I used with high

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【1AB6 /DK96でクリスタル・コンバータを】（活用編） Introduction I have made a prototype crystal converter circuit using a 1AB6/DK96 battery tube.　This circuit is located at the top of the Collins-type receiver and has a significant impact on the receiver's performance. I made a prototype for design verification.　The results obtained were good.　When the antenna was connected, it was found that the received signal in

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【電池管で受信機をプランする】（計画編） Introduction I started thinking about how I could make a receiver using a battery tube. There are two directions for that receiver. One is a single-super heterodyne format. It's just like what you'd find in a home radio receiver. The other is a double-super heterodyne format. The Collins type is especially wonderful in the double-super format. I decided to go for it. I've

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【1R5-SFをプロダクト・検波でテスト】（活用編） Introduction I tried out a product detector circuit with a pentagrid battery tube. The Battery tube 1R5 is the converter tube of the super receivers.　The product detector works on the same principle as the converter circuit. It should work well.　I used a ceramic resonator for the BFO, which is essential for SSB/CW detection.　While the frequency stability is a bit lower

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【1D8-GTでオーディオ・アンプを作る】（製作編） Introduction I'm making an audio amplifier with a 1D8-GT, which is a battery tube with a combined diode, triode and pentode. This 1D8-GT has been in my parts box for ages, so let's wake it up! The 1D8-GT was a vacuum tube made before WW2, so it's not as efficient as the battery tubes made later, but it's good enough for what I need.　It should work well enough as an

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【オーディオアンプ電池管：1D8GTを試す】（予告編：Preview） Introduction I am planning to build a receiver using a battery-powered tube. I have considered the converter and I-F amplifier circuits, so the next step will be the audio amplifier.　I intend to use an Australian made composite tube called 1D8GT.　I have started to gather the parts and start considering.　The circuit and the fabrication will be in the next issue

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【コンバータ管：1R5/1R5-SFを試す】 introduction I returned to the 1R5 on the battery tube to evaluate the converter tube again.　This was because I had a few 1R5s on hand and was interested in the differences between 1AB6/DK96 and 1R5.　The comparison was done in the same way as in the previous Blog.　The results obtained were without difference.　Converter tubes are not only suitable for frequency conversion

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【電池管のI-Fアンプを試す】 introduction I'm testing a vacuum tube, 1AJ4/DF96, designed for portable radios using dry batteries. Developed in the 1950s, these tubes are less efficient than those used in AC-powered radios.　Ingenuity is required to use them well.　The 1AJ4/DF96 circuit's I-F Transformer is key.　I've tested and made the Practical IFT for this tube. (2025.01.29 de JA9TTT/1 Takahiro Kato)　 【五極管:

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【コンバータ管：1AB6/DK96を試す】 introduction I'm testing a vacuum tube, 1AB6/DK96, designed for portable radios using dry batteries. Developed in the 1950s, these tubes are less efficient than those used in AC-powered radios.　Ingenuity is required to use them well.　The 1AB6/DK96 circuit's oscillator coil is key.　I've tested and made the best coil for this tube. (2025.01.14 de JA9TTT/1 Takahiro Kato)　 【七

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【それってトライバンダー！】 Introduction: I'm using a handmade mobile antenna that works on the 14 MHz and 18 MHz duo bands. It works well, but the other day I had a brainwave. I thought that if I shortened the radiant element on top of the antenna, I could use it on 21 MHz. I quickly tested it and it worked really well. I had an antenna for a new band without having to do any complicated work. Yes, the

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【FE-103Σスピーカ・システムの修理】 Introduction: I use speakers from a Japanese manufacturer called FOSTEX.　Its loudspeakers were quite old and the adhesion between the cone and the edge had deteriorated. I like these loudspeakers because they have a good sound.　I decided to repair it and use it. I use a rubber-based adhesive for repairs.　The loudspeaker was repaired well and I can enjoy the same good sound

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【シンプル・低周波フィルタの設計：補足編】 Introduction This blog is a quick guide to electronic equipment using filter circuits. First, I'll look at how we can protect electronic equipment from external stresses. Even the best semiconductors, like ICs, can be damaged by unusual currents and electrostatic discharges caused by differences in potential between devices. It's always important to have protection in place

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【シンプル・低周波フィルタの設計】 Introduction Do you think designing filter circuits is difficult? There are many different types of filter circuits. Some of the more sophisticated ones can only be designed with sufficient knowledge and mathematical skills. However, the filter circuits needed for general audio circuits and the radios used by HAMs can be easily designed. In this blog, I'll show you how it's

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【OP-Amp】 The OP-Amp was a great analogue invention ! Who said ? OP-Amp.はアナログの偉大な発明品 　　　　　　　・・・って言ったのは誰？ （ちょっと休憩します）　de JA9TTT/1 （おわり） nm

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【アクティブ・サブ・ウーファ：SW-P100の修理・その２ 】 INTRODUCTION I received a replacement edge to use for repairing speaker cones.　I purchased it from Amazon.com and it took 19 days to arrive from China.　The replacement edge was perfect.　The size is perfect for the loudspeaker to be repaired.　The loudspeaker units were replaced with new cone edges and returned to perfect condition.　And the sub-woofer are

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【アクティブ・サブ・ウーファ：SW-P100の修理・その１ 】 INTRODUCTION I believe my audio system lacks bass.　So I bought a used sub-woofer at a recycle store.　However, the sub-woofer was not in good condition.　The built-in speaker unit had a broken edge on the speaker cone, which was causing a strange noise and rendering it unusable.　The theme of this Blog is to try to replace the broken edge part. (2024.10.03 de

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【カメラとレンズの話 】 Prologue My digital camera, which I've been using for a while, has stopped working. The autofocus isn't working right. I checked and found that I had been using it for as long as 11 years. And I realized I no longer need a compact camera because of the excellent camera functionality of smartphones. However, it is sometimes difficult to take pictures with a smartphone camera. In the

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【五極管の低周波アンプ・その4】 INTRODUCTION The 6R-R8 pentode tube is a Japanese-designed vacuum tube that was employed in NTT's telephone relay network. It is believed that the prototype was the Philips E180F pentode.　This blog presents a comparison of the two pentodes as audio-frequency amplifiers.　It can be concluded that the two tubes have very similar characteristics. Therefore, they can be used in the

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【SRPP回路を使ったオーディオアンプ】 introduction I had never built an SRPP circuit with twin triodes before. So I gave it a quick try.　I selected three types of twin triodes. It depends on the value of the gain constant μ and the transconductance gm. The measurement results of my prototype SRPP amplifier are listed in the table. The results show that most twin triodes can be used for the purpose of this SRPP

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【三極五極管を使ったオーディオ・アンプ】 introduction I have a lot of Triode-Pentode composite tubes in my junk box.　They are all junk tubes from old TV sets. If I can make good use of them, I will be able to build an audio amplifier.　I immediately tested them.　The test results were very good. The test results are listed in the table below.　I will be able to enjoy handmade audio without buying new vacuum tubes.　I

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【部品：7mm角のコイル】 [introduction:] Many electronic devices these days are coil-less. However, it will be difficult to completely eliminate coils. Coils are indispensable electronic components, especially for us HAMs who build our own radios.　This Blog explains in detail how to make use of 7mm square shielded coils that were obtained as surplus. In addition, there is a distribution guide for the coils

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【AFアンプで五極管を・第3回】 introduction I have many pentodes for RF. This blog is a continuation of the previous one. This time I will build an audio amplifier with pentodes for RF with 7-pin mt tubes. Hopefully I can expand the use of those pentodes. I tested three types of pentodes: 6CB6, 6AK5, and 19M-R10. The 19M-R10 is an original Japanese tube made for NTT's telephone relay network. All of the

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【AFアンプで五極管を・第2回】 introduction I have a lot of pentodes for RF.　In this blog I will build an audio amplifier with 9-pin NOVAL based pentodes for RF. If they can be used well, they will expand their applications.　I tried three different types: 6BX6, 6EJ7 and E180F. They all seem to work well enough for audio amplifiers. They are very high gain and should be used with care. (2024.06.06 de JA9TTT

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