Questions tagged [transceiver]
Use this tag for general questions relating to transceivers.
103
questions
3
votes
0answers
35 views
SSB Single Conversion Superhet 2nd Mixer IF Termination on Transmit
I have a question about "best practice" in regards to how the 2nd mixer IF port is coupled to (in my case) a 20m double tuned filter on transmit.
I'm currently building out the transmit ...
2
votes
0answers
32 views
Diagnosing IC-7100 Drive Amp Bias | PA Won't TX
A faulty in vehicle DCDC charger has fed 16V or so into my brand new IC7100, killing the main board and preventing it from transmitting. I've replaced the mainboard with a brand new one however I'm ...
0
votes
1answer
52 views
How a reply system works on a aircraft transponder? [closed]
I'm trying to build a transponder ramp test for mode c and s of aircrafts for my degree.
I have a problem, I didn't understand reply system of transponde, how can I doba reply of a signal to test one?
5
votes
1answer
147 views
What is band stacking?
What is a band stacking register and/or band stacking buttons on a transceiver? And why would this be useful to an amateur radio operator?
Is using "band stacking" a current operating ...
0
votes
0answers
28 views
Setting the maximum Tx Power value for the USRP transmitter
In order to simulate the measurements on the computer (in the WinProp environment) I have to set the maximum Tx power:
To find out what the transmitter signal power is, I checked it on the spectrum ...
5
votes
2answers
1k views
What does ALC do on a transceiver?
What is ALC on an HF transceiver?
What are the disadvantages (if any) of operating using a rig without ALC?
What might be the difference between a good and bad implementation of ALC?
3
votes
1answer
298 views
Looking for origins of a crystal filter schematic used in uBITX
Here is a crystal filter used in uBITX transceiver:
I've never seen such a topology in any other transceiver and decided to invest some time in exploring it. Turned out it's quite interesting. Eight ...
3
votes
1answer
104 views
Kenwood TS 520 S Meter accidentally run without an antenna connected
I powered up my Kenwood TS 520 without connecting the antenna and after 1 hour realized it was not connected, after connecting the antenna I noticed the S-meter was not giving me a reading and I have ...
3
votes
2answers
271 views
SSB Transceiver Architecture - USB with Crystal Filter
I'm planning to build a 20m SSB transceiver and I want to get the overall architecture straight in my head first. Here's what I'm thinking so far, a single conversion superhet design with a 9MHz IF ...
0
votes
3answers
83 views
How can the waterfall still be displayed during transmission
I noticed that on some higher-end transceivers, the panadapter/waterwall is still being displayed during transmission. How is this possible? If the panadapter is part of the receiver, it should be ...
1
vote
3answers
421 views
What replaces the T/R switch in modern transceiver
I have been watching and reading about the time when receiver/transmitter were separated and T/R switches were used. Current transceivers are still sharing a single antenna to transmit and receive. ...
0
votes
0answers
33 views
Using radio for musical collaboration [duplicate]
I'd like to collaborate (e.g. play together) with other musicians in my local area and/or beyond.
Coronavirus has made in-person collaboration difficult. Latency makes internet-based collaboration ...
0
votes
1answer
71 views
Old 144MHz rig can transmit/receive signal but not voice
Situation:
I have an old 144MHz rig from the 2000's, an IC-271. I am trying to get it up and running.
Summary of the problem:
I can receive fine on the rig, except for from my HT.
I can transmit a ...
1
vote
3answers
161 views
Lab599 Discovery TX-500 connectors?
The Lab599 Discovery TX-500 is coming out soon. A lot has been said about that radio's use of weather-resistant proprietary connectors, but what are the actual connector types?
The antenna is female ...
0
votes
1answer
103 views
How does PTT from one two-way radio prevent input on another?
I'm very much a beginner with radio. I have a simple set of Baofeng BF-888S radios, and in my basic use with those, I got very curious about something: when you push the PTT button on one radio to ...
4
votes
3answers
1k views
What is the difference between RIT and XIT?
What is the difference between RIT and XIT? When would one use one and not the other for split (or other) HF operation? When would one need both? Which one is more useful for a transceiver to have ...
3
votes
4answers
826 views
What is the use of dual VFOs?
What is the value of more than one VFO in an HF transceiver?
Many novice rigs only have a single crystal oscillator, and a vast number of famous classic transceivers, HF kits, and QRP rigs only have a ...
0
votes
2answers
81 views
How Duty cycle affects transmission rate in RF module?
I planning to use RF module for communication of high precision GNSS module. So I am doing detail study on RF module. In one of the datasheets of RF module (part no: RFD868ux) mentioned that 'Duty ...
1
vote
4answers
187 views
Can't identify old Chinese(?) and American radio/telephone
I have searched image banks and Googled period radios, but I can not identify these old units. I picked them up overseas in SE Asia and I got them as projects to teach myself enough to challenge the ...
0
votes
2answers
474 views
Yaesu FT-817 Won't transmit Dig, SSB or CW
I have a problem with my Yaesu FT-817 it Won't transmit Dig, SSB or CW, But it does transmit AM, FM and Pkt on all bands. Does anyone know what the problem might be. The Radio receives fine on all ...
5
votes
2answers
883 views
World wide Radio Module
currently I am involved in a project were a data link is needed to communicate different devices. This is in one to many configuration and the devices are stand alone.
For this project there is need ...
-1
votes
2answers
122 views
Why can't we use a simple wire for receiving 2.4 GHz signals?
I wanted to build a small drone of my own as a hobby project. My old drones were broken so I wanted to salvage as much as I could to build a small indoor one. I wanted to use an Arduino, however, I am ...
4
votes
3answers
417 views
Need batteries for backpack operation
I am building an HF backpack rig using an Icom IC-706MkIIG with a Opek HVT-400B antenna. The specifications on the radio say 20 A draw at high power, so what size and type batteries would be suitable ...
0
votes
1answer
60 views
Problem with mAT30 ATU and FT-450D transceiver
Does this tuner work with this transceiver? Would appreciate response as I cannot get it to work!
1
vote
2answers
231 views
QYT KT8900D issue
A very specific issue this one. I bought one of these radios on an impulse because it was cheap but never really used it. Now, during lockdown my club has a nightly net on 2m so I built an antenna and ...
4
votes
2answers
827 views
Yaesu FT-991A: FM and C4FM modes don't work on HF bands
I bought a second-hand Yaesu FT-991A. It works pretty well and by the look of it's internals I don't believe it was ever repaired.
However I noticed one weird thing. When I try to use FM or C4FM on ...
0
votes
0answers
40 views
how do you tune blind? [duplicate]
I'm about to axe the display on my radio in pursuit of cheapness. However, I need to know, how do blind hams with older rigs tune to a station?
3
votes
2answers
368 views
Advantages of IQ mixer versus direct sampling SDR architectures?
What might be the advantages, if any, of HF SDR architectures that use a mixer between the ADC/DAC and RF, versus those that sample or generate RF directly (at 0 Hz on up) with a fast ADC or DAC?
Are ...
-1
votes
2answers
174 views
At what watt level is it safe to use metal strips for modulated signals?
In my working design, I have a transceiver TX on low power; Then boost it in a preamp phase in the back.
The way I'm sending the signals (RX and TX) through the radio is by a network of 1/8 to 1/4 ...
0
votes
1answer
573 views
Lowest cost portable HF radio with at least 100 W output?
My use case is intercontinental HF radio, and I am frequently traveling. Lugging a big rig is inconvenient and expensive ones get you into customs trouble all the time. So, I'm looking for a low cost ...
2
votes
2answers
139 views
What is a good step resolution in tuning and transmitting?
When constructing a new radio, what should your step resolution be and what is considered too much in resolution in frequency tuning and transmitting?
I'm talking about capacitor type tunning.
...
3
votes
1answer
145 views
What is this military radio?
Please help me identify this piece of equipment. It looks military spec, but don't know anything about it.
I want to look up some history about what it was used for.
Here are more photos.
-3
votes
1answer
148 views
Carrier telephone system adaptation
In amature radio, users can use what is called a phone patch to enable them to use a phone to establish connection to another party or user.
Phones are usually two wire and dont lend themselves to ...
3
votes
1answer
181 views
Can the external VFO input in a Heathkit SB-(100, 101, 102) be used to operate on frequencies outside the radio's normal range?
I've got a Heathkit SB-102 that I'm working on making operational (problems with transmit, receiver works just fine). This model radio has a 9-pin Molex connector in the back, intended to connect an ...
0
votes
1answer
58 views
Audio too high, how to troubleshoot
I am using a TYT TH-9800 with a 10 m half dipole antenna on low power (5 W) to connect to a WIN linked repeater (+5.0 MHz offset and 123.0 tone).
I made contact with two other stations and was told ...
0
votes
2answers
74 views
How should i go about building my first transceiver?
So i want to build my very own transceiver, not looking for anything worldwide, just local but i do have a background in arduino and some electrical engineering, what tutorials would you recommend?
4
votes
1answer
237 views
Does a UHF/VHF handheld transceiver kit exist?
I am a licensed ham looking for a UHF/VHF handheld transceiver kit. Unfortunately so far I was only able to find broken links, i.e. Ten-Tec used to produce exactly such a thing but they just don't ...
1
vote
2answers
130 views
If I parallel two crystal filters together, will that double the bandwidth? [closed]
Will the bandwidth be doubled ?
And will the impedance be halved ?
5
votes
2answers
253 views
Can anyone identify this military radio?
Hoping someone can identify the following military radio.
I spotted it at the curb and decided to make it a land-fill diversion project...
0
votes
0answers
86 views
Can I make a simple Tx/Rx antenna (Radio System) which will receive signal from BTS and broadcast/transmit it, and vice versa? [duplicate]
Consider a situation as below. I am stay in a farm field, which my house is 9.4km distance from the nearest and the only one BTS (Base Transceiver System), a cellular antenna for transmit and receive ...
1
vote
1answer
64 views
Can the transmit and receive functions of a boat anchor transceiver share the tank circuit?
I'm starting design work on a two-tube (two-valve, for those who prefer that term) reflex-regen receiver that I hope will cover AM broadcast through 160m-10m -- both amateur bands and those "in ...
1
vote
1answer
377 views
Power output of KT8900
Any ideas on adjusting the low power output of the KT8900. The output tranny has a max rating of 12V and specs are centred on 7.5 volts. Yet they try to run it at 13.8V?? I want to reduce the output ...
5
votes
1answer
116 views
How long can a transceiver be unused before I have to use a variac?
I have an old TenTec Argosy II that hasn’t been powered up for 20 years.
How long can electronics go unpowered before I have to worry about the electrolytic needed a slow power up with a Variac?
2
votes
4answers
1k views
What is a simple kind of amateur radio transceiver I could try to build, as a beginner?
I am new to amateur radio, and I'm trying to learn the basics of the hobby.
I would like to build a simple radio transceiver from scratch (i.e. not from a kit).
I have searched the Internet for ...
2
votes
1answer
179 views
Where does this common spurious transmission come from? Is there a quality difference?
I decided to see what my ham transmissions look like on an SDR and was kind of shocked to see how much leaks out. The waterfall display is split between two handhelds during transmit. There are a ...
1
vote
0answers
116 views
2GFSK 9600bps Transmitter and amplifier for 433 MHz
I'm looking for a reliable, however cheap solution for ground-space communication. I need at least 50W of transmitted power with 2GFSK modulation at 70cm band (433 MHz). Transmission will be done ...
5
votes
2answers
476 views
Share wide band antenna with multiple transceivers
I'm trying to incorporate several transceivers on my board design; I need
WiFi (2.4 GHz)
SatCom (~1.6 GHz)
RF (~900 MHz) and
GNSS (~1.5 GHz).
I need to combine them into one antenna. I found a wide ...
2
votes
3answers
705 views
Can I use two yagi aerials back-to-back for a bi-directional system?
I need to create a setup where I have three radio transceivers (869.4MHz) setup in a straight line.
I need to be able to communicate, in both directions, from the centre pole to the outside two poles,...
14
votes
3answers
2k views
WWV, WWVH, and WWVL may be shut down. Are there any alternatives?
The US government is proposing to shut down the NIST standard time and frequency stations WWV, WWVH, and WWVB in Colorado and Hawaii.
If that actually happens, are there any free or inexpensive ...
4
votes
2answers
466 views
When was the first radio transceiver (transmitter/receiver) built, and by whom?
I'm really passionate about signals and communications ever since I was a child where we "built satellites" - little did I know that it would become part of my future. So here is my first question:
...
