Technical Articles

What is LoTW, Why Should You Sign Up for it, and How Do You Use it?

When I started out in Amateur Radio 40 years ago this summer, there were basically three ways to exchange a written confirmation of a contact (a QSL card):

Mail your card directly to the station and request a card from them. Etiquette often dictated including a way for the station to return their card to you without them incurring any expense:

  • Stations in your country­: include self-addressed stamped envelope (SASE)
  • Stations in other countries: include international reply coupons (IRC) or cash (often called “green stamps”); IRCs are no longer sold in the U.S.

Send your card and request to a station’s QSL Manager (a third party who would handle QSLing for a very busy station). This request also usually involved a SASE, IRC, or “green stamps.”

Use a QSL Bureau (often written as Buro). In the U.S., the ARRL runs a QSL Buro that sends out QSLs in bulk to other buros worldwide, receives incoming cards from worldwide buros, and sends them on to volunteers who forward them en masse to stations using the buro.

All of these methods had traits in common:

  • Filling out and sending QSL cards
  • Use of postal systems to move physical cards around the world
  • Money outlays for QSL cards, envelopes, postage, and buro fees
  • Waiting time while cards moved slowly and often inefficiently across the globe

In 2003, the ARRL introduced an electronic confirmation (QSL) system called Logbook of The World (LoTW). This system was designed to avoid many of the downsides of physical QSL cards and their movement from place to place. One of the primary goals of the plan was to provide secure authentication using cryptographic key distribution. An amateur’s computer-based logbook, in ADIF or Cabrillo format, must be “signed” using a key obtained from the ARRL. Logbook data includes callsigns and locations of stations, contact time, frequency, and operating mode. The ARRL assigns keys to U.S.-based amateurs who appear in the FCC licensing database and to non-U.S. amateurs who provide alternate proof of identity.

Some of the advantages of using LoTW include:

  • No need to purchase and fill out QSL cards
  • No postage or buro costs
  • No SASEs or “green stamps” required
  • Easy upload/download of contacts and confirmations from most logging software programs
  • Less waiting time; can take minutes versus months or years
  • No lost cards, sorting, or storage issues
  • Acceptable for most major ARRL awards and a few CQ Communications awards

There are also a few disadvantages:

  • No physical QSL card to display in your shack or show other hams
  • Not acceptable for all award programs
  • Requires some setup time and effort to use
  • Not all stations participate
  • Some costs when you choose to use confirmations to apply for awards

As you can see, the advantages of LoTW far outweigh the disadvantages for many stations. Some of the disadvantages can be taken care of by using traditional QSLing methods or other electronic QSL services (EQSL, OQRS, etc.) to supplement your LoTW activity.

The bottom line: LoTW dramatically reduces the effort, cost, and time to receive confirmations. Many contacts made today will be confirmed in minutes. Cumbersome mailing and sorting systems are no longer required, and LoTW is free for all licensed amateurs.

Before we get started, here are links to two definitive guides on LoTW

Preparation for Using LoTW

  1. Download and Install TQSL software from the ARRL website
  2. Install TQSL
  3. Run TQSL
  4. From within the TQSL program, Request Callsign Certificate
    1. From the top menu, select “Callsign Certificate”
    2. Click “Request New Callsign Certificate”
    3. Complete the information requested on subsequent windows
    4. Submit your request electronically
  • Wait for ARRL to mail (snail mail) postcard. Card will only be mailed to the address you have on file with the FCC, so update FCC information first if necessary. Note: the procedure is different for hams outside the U.S.
  • While waiting for the postcard, you may want to start transcribing paper logbooks into a software-based logging program. For more information on general logging software, view the ARRL “Amateur Radio Logging” Video or Slideshow.
  • Once you receive the postcard, you can complete the registration process and begin using LoTW.

Using LoTW

How you upload your contact records and download your QSL confirmations from LoTW can vary widely depending on the logbook software program you are using. Although you can use TQSL directly to sign any ADIF or Cabrillo file from a variety of Amateur Radio software, many hams will actually use functions built into their logbook software to sign and upload contacts to LoTW. Each program works differently, so please read the documentation for your chosen software. Many of the programs can automate most of the operations of uploading new QSOs and downloading new QSL confirmations.

What Goes on Behind the Scenes

To be successful with LoTW it is helpful to understand a few things that happen behind the scenes. The process of QSL confirmation involves an electronic matching process. In the diagram, we see records submitted by two stations: K8ZT and N1UR.

In this example, LoTW has imported a log uploaded by K8ZT. One of the K8ZT QSOs was with N1UR, who has previously uploaded his log to LoTW. LoTW compares the QSO records. Provided there are no significant discrepancies, the QSO is now noted as confirmed for both K8ZT and N1UR.

K8ZT and N1UR can use the confirmed QSO to apply for DXCC or other awards, just as if they had exchanged QSL cards, but the entire process may have taken place just minutes after the QSO. In contrast, QSL cards generally take weeks, months, or years to arrive, longer still for an authorized card-checker to determine by eye whether the cards and QSOs are legitimate.

What are possible discrepancies? All records must be signed by a valid, unexpired TQSL certificate. Both records must show both the same callsigns, band and mode; the actual frequency on the band is not considered in this process. The date must match and the times must match within a designed window but do not need to be precisely the same.

Other confirmation information comes from each station’s Station Location settings in TQSL. These can include DXCC Entity, Grid Square, ITU Zone, CQ Zone, State, County, IOTA (Islands On The Air), and/or National Park/Monument. Other information about the contact, like power level, names, RST, etc., is not included in LoTW.

What else can LoTW do for you?

By logging into the LoTW page, you can view any of the QSO records you have uploaded, QSL confirmations, Logbook Awards, and more. Logbook Awards include your progress for DXCC, Worked All States (WAS), and VUCC (VHF/UHF). You can also apply for ARRL Operating Awards like DXCC, WAS, etc.

For additional information on LoTW and other online QSLing services, see my slideshow, “QSLing in an Online World,” or video presentation on Amateur Radio Logging.

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